I cut out my tufted piece without glueing and it curls up
When you cut out your tufted piece from the frame without glueing it it will start to roll itself up.
There are two options to handle this.
If you are making a big wall piece you are most probably going to glue or staple it on a wooden plate. Then you don’t have to worry. But you can make your life easier by ironining the rug as described below.