What I normally do is put unit in place then mark where I want the glue to stop with the end of comb on your forehead it will leave a little red mark there for awhile this will give you time to apply glue and stop at the red marking on your forehead...it you go past the lace then all you have to do it push the lace down with the teeth of the comb and then take some 99% or lace release with a small Qtip and remove the excess glue. Hope this helps. Cheers