I have a pair of incontinence pants for wamming and I have been less than successful whenever I try them.

The first time I made xanthan gum gunge, about 10L worth, and the pants could not stay up. The gunge pooled between my legs before the weight was too much.

The second time I put a lemon meringue pie on my butt and it too fell between my legs, not staying against my flesh much at all.

Do you have any advice? I can't really get a smaller pair as the leg holes are already very tight. Would suspender clips tear the plastic? is there some way to keep the mess against me and not hanging tantalizingly below me?

I would go with tighter underwear - boxer briefs, perhaps, or speedos.

You could also wear some lycra shorts over the top to help keep everything in place.

Perhaps a Lycra wrestling singlet will do the trick? You can fill up the singlet to the brim and have minimal leakage depending on how you've positioned your legs.

I'll post a pic of how the singlet just traps all the goop. You can fill it up even more when you're sitting and have your knees up.