mitchec

Hi there, I am very new to this and wanted to get some advise, I have been trying to vacuum form action figures for some time now, they come out OK but the plastic is way to tight around the figure, I am using PVC. I wanted to see if anyone could give me any tips as to how to create more room inside the plastic so that the figure has some breathing space inside - i.e covering the figure with some kind of material? or using a riser? what works best - any help greatly appreciated. Chris