1- Take paneling off remove crappy oem clips and fasteners than are replaceable.
2- Clean with something that evaporates like windex
3- get rid of excessive surface material and clean again with windex
4- use rubbing alcohol to clean the door one last time. this can also be done after step 5 if your messy or your cavities are not that well enclosed.
5- this spray is amazing. but first make sure u have everything done inside of your doors that needs to be done, ie tightening bolts screws, wiring ect. Carefully spray inside door (make sure the window is up XD) and not on the surface that your going to dynamat. Always buy new panel clips. They are not screws and wear out after each use.
6- most panels have a layer of plastic between them and the metal. dont ruin them too badly as you may use them to trace your cut line on your matting. I looked around for rollers and really the best thing i found turned out to be a 3-4$ bed caster(wheel)
work your matting from bottom to top to avoid unwanted adhesion wear gloves this crap is sharp as a razor if your not careful.
7- Don't forget to pop holes through for your panel plugs. install speakers after the mat is in place. i leave excess matt on all edges usually. i used the excess around speaker to secure the wires that otherwise would flop around in the door.
8- dont be lazy do it all. if you have loose trunk lock or window rattles excessively just add a hard piece of rubber tubing over the metal loop that catches the latch. shouldnt need very much. The tighter it is the better.
9- dont be lazy!!!!!!!! i tore everything i could unscrew apart and matted it. This happens to be the lid to my center console. you can knock on it now and it sounds like very solid like hitting a wet log, before it sounded like an empty luch box.
10- you took it apart so you should know how to put it back. Its very easy if you have time.