If you do all tape (or tape/glue), then you need to use the
@Noah process. You place a tape on top of your head, spray with alcohol, place the system, use a hand-held-mirror to see the back, make sure it's all set, front to back, left to right. You have 60 seconds before the alcohol evaporates. Press down on the system where the one piece of tape is... roll the back, forward, peel and attach, then do the front. You get a perfect attachment every time.
If you are doing a full-head bond, then you can spray your entire head with alcohol... and then place the system.
This method has been discussed and explained... ad nauseam on this forum... just search.