After having kept an Iguana, several crested geckos and now a chameleon (often considered one of the most difficult reptiles to keep healthily in captivity) I feel I have a large enough body of experience to share some with you guys. I spent a lot of time and money making mistakes along the way so I thought I could write this in the hopes that others could benefit from it and maybe lose less than I did getting to where I am. This guide is for reptiles in general and does not cover snakes as I have never kept one nor done enough research on them.
Step 1 - Choosing the reptile that is right for you.This is a general guide and only covers some specifics. When you have decided you want to add a scaly friend to your family you will want to work out which species and genus is best for you, your available space and the country and climate you live in.
The most important thing here, and I can't stress this enough, is research, research research. Before you get your new friend you want to make sure you know as much as possible about it's required care. Some animals are more open to being handled but they are few and far between in the reptile kingdom. The majority of reptiles are display animals. They may become more enamored of you over time but often they will never be truly tame.
Arboreal reptiles will have very different requirements to desert reptiles for instance. Find out what temperatures your animal needs and make sure you have everything set up before you get him to save time and stress to your new friend. Remember - stress can kill. Particularly in more shy reptiles too much stress can cause them to stop eating or drinking or make them behave in unnatural ways which can cause harm to them. This brings us to our next step -
Step 2 - Making a home.Rule number one here is - pet shops suck. In general the setup that a shop will sell you will not be optimal for the reptile you have chosen to keep and in some cases may even be harmful to your animal. Remember - research. Skimping on time spent making sure your reptile's home is ready for him/her will result in stress for both of you and possibly more money spent than needed fixing the problems. Buy the pieces you need and set it up yourself, often it will be cheaper than a store setup and you will learn a lot about your animal and it's requirements before it arrives.
Ensure that you have the correct temperatures and humidity in the right places before you get your animal. To this end you will need a hygrometer and a thermometer. Most commercial hygrometers are fine for measuring ambient RH (Relative Humidity) but many thermometers sold by the pet trade are not adequate for reading temperatures in specific spots of your enclosure. A laser thermometer is best for this and can measure almost any spot in your cage instantly. These are actually quite cheap if you look hard enough. Popular auction sites will have them at around £5-£10 (approx $7-15). This is not something that you should take lightly. Temperatures are important for reptiles to regulate their body temperatures and digest their food. The wrong temperatures can make your animal stop eating, become constipated or impacted, become dehydrated and cause undue stress.
Also important in the enclosure is lighting. For most animals a regular 40-100W household bulb is fine to create the temperatures needed. Just as important as basking lights are UVB lights. Many reptiles need UVB to help them make vitamin D3 which helps them use the calcium they get from their food and supplements. Find out what your reptile needs and make sure your UVB bulb meets it's requirements. UVB bulbs should be changed every 6-8months minimum, even if they are still giving off visible light they may not be giving off UVB.
For Humidity you will need at the very least a hand spray bottle. Again - research. There are automatic misting systems available (Mist King or Aquazamp are my recommendations for these) and I highly recommend you get one if you are keeping an arboreal reptile and especially if your reptile does not drink standing water.
Finally the type of cage is important. There are generally two types of cage used to keep reptiles. Screen enclosures (Reptibreeze recommended) or Glass enclosures (Exo-Terra). If the ambient temperatures and humidity in your house are close to what is required for your reptile it is almost always better to get a screen cage. These allow for greater ventilation and can help prevent your reptile suffering from bacterial or UR (upper respiratory) infections. If the temps and humidity in your house are too low for your reptile, as is the case for most people who keep reptiles native to desert climes, you may have to get a glass cage. If you do then make sure it provides proper ventilation to prevent the air from getting stagnant and to help avoid the health issues mentioned before.
Step 3 - Getting food readyFind out what your reptile eats and keep a good stock of it. For herbivores you should ensure that anything you buy for your reptile is free of pesticides and contaminants. This means buying organic where possible, washing everything thoroughly and removing the peels from fruits and vegetables that have them. As a side note - if you are intending on keeping crested geckos you may do well with Repashy's Crested Gecko Meal Replacement Program, this will make your life much easier.
If your reptile is an insectivore then you will need to know about gutloading. Gutloading is the practice of feeding your insects nutritious food so that the nutrients, vitamins and minerals can be passed on to your reptile when he/she eats them. Remember - a healthy cricket or superworm makes for a healthy reptile. There are many premade gutloads available on the market. Research and find out what contains the best mix for your animal or even better make the gutload yourself.For my chameleon I liquidise carrots, oranges, collard greens, mustard greens, kale, apples, bran, oatmeal, alfalfa and bee pollen and then freeze the resulting mixture into icecubes to be thawed and fed to my insects. This is much cheaper than commercially available gutload.
Most captive reptiles will require some kind of supplementation as well. This means calcium powder (with or without d3, see what your reptile requires), multivitamins and other supplements. Know your reptiles requirements and keepo a calendar so you know when to give him/her what.
Step 4 - Getting your reptile... finally 
Once you have their house and their food ready for them it is finally time to purchase your reptile. Once again - pet stores, in general, suck. If you can you should look for a reputable breeder online. If you can't find a reputable breeder close enough to deliver the animal to you you should be careful about what you buy from a shop.
Firstly you should make sure that the animal you are getting is captive bred and not wild caught. Wild caught animals often have parasites and other health problems that are not immediately visible but can present later with serious consequences and huge vet bills. Next you should check that the animal is in good health and being well looked after in the store. If a store has a poor setup and is mistreating it's animals the temptation is to 'rescue' the animal from the store. Though this is a noble thought at first the problem with it is that when you buy the animal it will just be replaced by another which will be mistreated in the same manner. By refusing to buy the animal you don't feed into the systematic abuse suffered by animals in the pet trade and possibly cause the shop owner to think twice about how they treat their animals. Remember - the pet trade is about money and a missed opportunity for a sale can have an impact whereas buying the animal only encourages further abuse.
Some signs of bad health that are common in reptiles include - sunken eyes, broken claws, misshapen limbs or deformities, scratches or tears in their skin, shaking or wobbling side to side, bobbing their heads, milky or dull looking eyes and a loss of appetite. Ask the store owner to feed the animal so you can watch it eat.
Juveniles are often much better than adults. They have not had time to become unhealthy and you can often reverse any health problems you may later find. In older animals this can be hard to do.
Step 5 - Moving inwhen you get your animal home it is best to get them into their enclosure, provide them with food and water and then leave them be for a while. The temptation is to try and bond with your new friend. Don't. Leave your new friend to explore his/her home and disturb them as little as possible for the first week. Moving for people is said to be the most stressful thing you can do. For a reptile it is worse. Let them become acclimated to their enclosure and slowly get them used to your presence, invading their new territory only when you have to to clean or change their food/water. After the first week you can offer them small treats by hand, slowly they will become less frightened of you when you come close and after a while you may be able to handle them (depending on species) for a time. Always lift a reptile from underneath, slip your hand below it's chin and front legs and allow it to climb onto it. Never grab it from above as this will scare the animal and all the time you've spent handfeeding it will go to waste as it will no longer trust you in it's territory and you'll have to start all over
In conclusionThis is a very generalised guide and the biggest message I hope people get from it is research, research, research. Don't trust the pet store. Find out for yourself what your reptile requires. Some of the best places to go for this are Chameleonforums and Reptileforums. The people there are often quite knowledgeable and will help you with choosing your reptile and getting everything ready for them. Look up caresheets for your particular animal and get everything else ready before you buy your reptile.
I hope this is helpful to some of you who are thinking of keeping a scaly pet. If you have any questions or would like links to care resources, shops, breeders or vets then feel free to PM me. Good luck and may you all find the pet that is right for you
