Anyone know how to stop a side stitch?

This is a problem I get occasionally only while doing jumping jacks. I don't know what the problem with jumping jacks (or any of the jack varieties like fly jacks, up and out jacks) is, but it's the only time I get a stitch- usually happens under my left ribcage. Happens during warm ups as well as during the main workouts when I'm already warmed up.

Any tips on what to do if I get one (normally I either power through the interval if it's almost over, but sometimes I have to stop jumping and just wait a few seconds for it to go away) or how to stop it when I feel it coming on?

Edited