I also wondering how to perform this, never perform trades before, but would love to try in order to hunt down items that I want, but the items that I intend to acquire through trades are small items like keycaps mostly.
So unless the partner is a reputable person, generally use the paypal method?
Because shipping out at the same time is kind of difficult, what if you both agreed to ship on let say, tomorrow, but then if the partner is a scammer and tried to cheat on you, he can come up with whatever reason to say like "Oh, I woke up late etc. and have thus missed the time to post office bla bla bla"
that is my greatest concern though...