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.
Follow this link to learn about finishing options.
If you have a rather small piece you can hang it without a wooden plate.
To make it go flat again you can simply iron it with a damp towel on top or your steaming iron in case you have one. This will help the yarn to find its proper shape.
DO THIS BEFORE YOU DO ANY GLUEING!