Hi there, --as a matter of interest, [forgive me if you said so already] are you doing an all-over bond or just perimeter and using tape or glue ? I assume glue because it took 3 hours to do the several de/re-bonds...... the marking of dots as Hersute has demonstrated can be a huge help when you`re new to this , or even not so new ! I assume you are shaving that sparse hair off ` out of your way` so to speak ? Bonding materials will stick far more effectively to scalp-skin ..growing [ albeit sparse ] hair, will interfere with your bond and lead to an earlier-than-planned de/re......also, to avoid the frustration that you experienced, if / when you make an error placing the system like that, rather than spend hours as you described, why not give yourself a ` break` from it for a day or two and once you`ve cleaned off the bonding material from system and scalp, why not go for a ` quick fix` and just use Got2bglued spiking glue to pop your system on...ok, so it won`t hold your system on for more than 2 or 3 days, but it`s a way of getting out of a bind quickly and avoiding 3 tedious hours of mess and frustration ....as time goes on, you`ll have this down to a fine art, or very near to it ...in the early days, you`ll have events like this and the likes of Got2bglued really comes into it`s own in such situations, especially if you`re in a hurry to go / be someplace and can`t afford to be wasting time and getting annoyed/ frustrated into the bargain....it`s water-soluble too so it`ll simply release under the shower-head and rinse off without shampooing ...... just be aware that it can sometimes leave a white-ish mark on some areas of the lace, but not enough to be of real concern. Don`t lose heart ..the worst bit is over for you now ....you`ve made the leap so just stay with it ....kind regards.