you can use blue tape if you use it correctly. A method i have used before is draw out the hairline with a makeup pencil or whatever method you use. than attach the blue tape to the scalp. U can even stretch the tape out as you attach using the st30 attachment method etc. once u have the tapes on ur head, u take a tape backing and rub it in a downwards motion on the tape to dull any shine. It works well. blue tape can be very invisible if you know what you are doing.