I had this same problem, then....
I cut out the freezer paper and iron it to the right side of the fabric, then cut the shape out keeping a 1/4" seam allowance all around, then I use elmers washable stick glue to hold it to the backing fabric and I turn the edges under with the needle as I sew. Saves so much time
I use the edge of the freezer paper as my guide and the paper keeps the piece straight. PM me if you have any questions. When done sewing I remove the paper