If I have drawn my pattern then I will glue it to plastic and cut out. If from a book or magazine I will do the same but only before checking the copy with the original. Some copy machines slightly distort the original.
If I am only making one, two or three of a shape then I will cut the pattern from the paper. Put some double side tape on the back and place on fabric and then with the ruler will add the seam allowance as I cut.
Anything you use should be strong enough not to distort the edges when marked.