pulling fabric technique

[65Buick]

I've learned when you're stretching fabric to use the palm of your hand and not your fingers. This is sage advice. I have also learned to lightly stretch one way before doing the stretching around corners etc so that the fabric does not pucker.

My question is: has anyone developed a tool that fits into the palm of your hand so that the fabric is even more evenly stretched? Because there is still an ever slight variation in the areas of the palm.

I want my products to look like they came out of the factory, not like it's good but you can still tell it was done by hand.