Best way to stop jaw from moving while on stims?

Everytime I do meth, my jaw constantly moves side to side, like a cholo. Anyway to stop this? Not only is it such a give away, but sometimes I wake up with blisters in my mouth from biting. This isn't just with meth though, happens with MDMA and Addy as well. But I plan on doing meth tonight so that's why I asked. Thanks.