Fold the bottom of the curtain up 1 inch all the way across. Secure the satin to itself using sewing pins every 4 inches or so along the edge of the fabric.
Place the curtains on an ironing board and turn your iron on to the "Warm" setting.
Place a protective pressing cloth over the satin and iron the pinned bottom edge to press the fold flat. The pressing cloth protects the synthetic fabric, which can pucker and melt under direct heat.
Create a straight line of stitches using a needle and thread or loaded sewing machine across the top edge of the folded fabric. Cut the needle away using a pair of scissors and remove the sewing pins.
Repeat the process with the right and left side of the curtains, but only folding the edges in 1/2 inch instead of 1 inch.