I do a lot of T-shirt quilts. I bought 2 pressing sheets ( Teflon non-stick) to use. I put pressing sheet down on the ironing board. Then lay down the t-shirt, print side down on the press sheet, then the fuse web ( pelon 906f) with sticky side down on shirt. Then a damp piece of thin muslin. ( I put it in a pan of water and squeeze out as much water as possible)That will help the fusing process. Then put another pressing sheet on top of the stack.
The pressing sheets have been well worth the price. The ironing board and the iron are always clean.