Hi, everyone i just received 2 dz of transfer from Proworld Inc. Real nice. I did one shirt and its looks great. here is the problem how do i know when the pressure of the heat press is set to medium or high? what is a PSI? I tried we the same design but i think change the temp and it was a disaster. please help i'm trying to start a business and its hard to start doing t-shirts i don't want to quit but i can't still wasting money on trying and error. any help i will appreciate