Hey Samspauld8

Yeah it can be tricky when starting off.
What i do when attaching the back i hold the hair back with some small hair clips then standing in front of the mirror and holding a small mirror with one hand up behind my head i carefully can see where to clean or apply the adhesive using my other hand. you get good with practice.

These are the clips i use small plastic crocodile there only about 3cm long.