I hate tailor's chalk, I prefer not to apply pressure to my fabric because things can shift. And it's big and bulky. (When I say "tailor's chalk" I mean the stuff actually labeled as "Tailor's Chalk" in fabric stores...which is a triangular wedge. I don't care for the non-mechanical pencils, either.)
Try a Clover Chaco Liner. It's a dispenser with a tiny wheel in the tip that leaves ultra-fine chalk dust behind. The dust comes in different colors. The only thing is that it can be trickier to go around curves with it.
I also use the Dritz fabric markers: the purple disappearing ink markers and the blue Mark-B-Gone markers. I haven't had trouble with those staining synthetic fabrics. Sometimes the marks persist if you don't get the fabric wet enough and you'll find ghost color, but then I just dunk the entire thing in water to really saturate it and that works fine. (Just don't get the pink version. I had a bitch of a time getting the pink ink to disappear.)
FF9 cosplay? Hit me up!
2014: Anime Los Angeles, Anime Conji, and whatever else falls into my lap
I now have a Tumblr
. Sometimes I use it.