Here's a neat trick for marking patterns,paper punch a hole, where you need something marked if designing extra features on your paper pattn.Put a pin thru the other section, then turn over & mark that area.Use a kids crayola washable marker.Dab a drop of water to remove marks.Violla!
I found this useful when making curved welt pockets,drawing the welt first on the pattern, then punch a hole in 3 areas,joined the dots with a french curve ruler.