The Las Vegas Airport is one of the most manageable in my experience. Large but not huge, McCarran is fairly easy to navigate, especially if your arrival and departures are using the standard Taxis or Shuttles. City bus service in and out of McCarran is a little trickier as the bus departures are from level 0 and not signed well. Unless you are really short on cash the best option will generally be a Taxi if you have more than 2 people or the comfortable $5 shuttles which leave from just outside of the baggage claim area and deliver you to the door of your hotel for $5.