carol45

I use soap slivers to mark on dark fabric; a damp cloth, or steam iron removes the soap marks.

ragamuffin

If you are outlining the lines or squares in a quilt, use the blue painters tape. It does not leave any residue and comes off very easily. I would quilt at the edge of the tape. Try it first.

JustAbitCrazy

baywinds, That link doesn't work but I can tell that's not it. Miracle Film is a heat away stabilizer made by Marathon, who also make thread. It is a lightly frosted clear plastic with perforations, so it tears off very easily. It is made to be removed by hovering a hot iron over it, which makes the plastic melt into little balls which can be brushed off, but it tears away so easily I've never had to do that. When you mark with a fine sharpie, the ink must be thoroughly dry so the needle doesn't transfer the color to the quilt top. Either let it dry overnight or cheat as I sometimes do by drying it with a hairdryer set on low or no heat (remember, it's "Heat away", no high heat!).
I just read the post about the red sharpie. I have always used a fine black one, with no problems. Don't know if color makes a difference.