I'm going wayyyyyy back! To help in preventing the waves when sewing, you should pin your satin to tissue to sew. Remember though you don't want to place your pins in your satin area that'll show and will not go away, place your pins where your seam allowance is. As for the fraying aspect, you could try using pinking shears or pinking rotary cutter. This should help some with the fraying.
Good Luck!! :thumbup: