tip #1 patience.
tip #2, hair dryer for this is not the best tool, i would recommend a glass heating plate. this will heat equally the back glass of your phone. then you can use a very thin ic removal blade just to unglue the glass from the frame. (you just need lica 1/2 inch so you can insert a metro card, careful the glass breaks pretty easy). then use a typical metro card and with a syringe inject little isopropyl alcohol where you are moving the metro card. reheat the back glass as needed. check where ir the fingerprint scanner flex cause you can damage it easily. also careful with the NFC antenna qi charger coil.
Good luck
PS. most youtube videos will show you an already removed glass, and remove it again as they record, looks pretty easy.