why glass = you can removed the glass to remove your print, you can clean it.. with a bolted down build plate this is a problem
why hairspray = it helps prints stick better to glass over other methods
why pull the tape = if you use glass, you'll want to, that's juts another thermal barrier you will want to remove.
as far as usage on a specific slicer, i would suggest youtube. lots of helpful videos on how to use them.