Removable Fabric Markers 
Obviously, we need fabric markers.  The marks should be removable, just in case some of the appliqué doesn’t line up perfectly.  I have two favorite markers:  one for light fabrics and one for dark fabrics.

Light Fabrics
“The Fine Line” is a water erasable pen that marks in blue.  I like it because the tip is very fine and it makes a nice, thin line.  You can also get an eraser pen, which removes the blue markings.  This is great for fixing up mistakes!  But I find the best way to remove the lines completely is to immerse the block in water.  Spritzing or dabbing the lines with water appears to work, but often some of the blue returns once the area has dried.

Dark Fabrics
Clover’s white marking pen is erasable with a hot iron as well as water.  Just take note that the marks take a few seconds to appear, so be patient.  The white lines show up well on the darker fabrics where a blue line wouldn’t.  Sometimes, I go over the lines a second time to make the white lines brighter.  Mistakes are easily corrected by ironing over them, but just be careful not to iron your marked fabric until you’re done with the lines!

Sandpaper Board
A sandpaper board is incredibly useful for marking fabrics.  It is placed underneath the fabric to keep it from shifting.  You can purchase a sandpaper board specifically for this purpose, or you can make one yourself.  Simply attach a sheet of fine grit sandpaper to a sturdy mounting board.

Fabric on sandpaper board