15 amp minimum circuit capacity means you can run a length of 14-2 wiring and use a 15 amp 2 pole breaker.
Personally,I would use 12-2 on a 20 amp 2 pole breaker.On the panel door or the deadfront(metal breaker cover) the acceptable breaker types will be listed,just buy one of those.The white and black wires go on the breaker, the bare grounding conductor on the terminal strip with the rest of them.Your compressor should have built in motor overload protection and a disconnect on the unit.If you wire it permanently,it's best to use a plug and receptable so the unit can be easily moved if necessary.
Best to shut off the main breaker, practice a few times unplugging and plugging in the new breaker so you get a feel for it.And tighten all screws and or wires nuts firmly,make absolutly sure the grounding is good.
