The best way to check the relief is by putting a capo at the first fret and then fretting the string at the body (12th or 14th), and looking at the string height at the 6th fret. For normal playing, the thickness of a normal business card between the fret and the string is sufficient relief. You might be able to get away with less - maybe considerably less depending on how "energetically" you play - but more will just make fretting more difficult.
Action height and neck relief are two different things although neck relief affects action height. The procedure is to check/adjust neck relief first. Once that is OK, THEN action height is adjusted for the preference of the player/style of playing. The action height is changed with a saddle and/or nut adjustment OR, on a Taylor, if you prefer, you can have the neck shim changed to provide the action you want.
