I have decided after much experimentation- that these are my best friends for sewing! For some reason I have always just done withouth, but now I am starting to think that my sewing life is going to get much much easier all of a sudden!
There is a magic little chalk marker that I have found that has come to be a big favorite of mine. It has a wheel in it and and loose chalk and you roll it over what you want to mark and it works like a charm. It is refillable and comes in red, blue and yellow washes out or brushes off very easy if needed to correct a mark.