Its a big trade so i want a mediator.

Make a thread for the trade.
Then hit the "Request a Mediator" Button on top.
Make sure both you and the other trader posts and confirms the deal in the thread.

The mediator will then contact you as soon as they can.

I hope this helps!

The person who created the trade topic can request a mediator above the first post. Next to "Track Topic"

You can find more information in here - https://forums.d2jsp.org/info.php?p=11

So what if the person who made thread wont request mediator

Then the trade cannot happen if he doesn't request a mediator willingly. You can try to negotiate with him to request a mediator of course.

If something looks shady and he will not use a mediator, don't do the trade.
If it looks too good to be true, it probably is

This post was edited by Culinary on Dec 13 2018 03:24pm

If you dont feel comfortable completing the trade on your own and user you are trading with will not request mediator I would not continue through with the trade.
Maybe offer to make your own topic and you request the mediator yourself.

Meds are the best option

Then you're about to be scammed...

you request a mod by making your own topic