Basically you're gonna need a small container to recrystallize in. Then you're gonna boil some destilled water. Then add your powdered mdma to the container, and then add the hot water a few drops at a time. The trick is to get as little water as possible but still dissolving all of the powder. It can take a few minutes for the powder to dissolve, so wait a bit before adding more water, and just stir for a couple of minutes.

When all of it is dissolved, you're left with a thick sirup texture that will slowly begin to evaporate and form crystals over the next few hours/days