Using pace zones in GARMIN 205

Another Garmin thread, sorry. Using RW training calculator I know my easy, tempo, VO2max pace but how would you store that in the GARMIN? Pace zones require an unpper and lower limit so do you call the predicted pace the lower and enter the upper as the lower limit of the next band? For example, easy = 12:04 and tempo = 10:04 so zones are easy 13-12:04, 1/2 mara = 12:04-11, tempo = 11-10:04. Or should the time predicted be used as the average so that the zone for easy = 12:30-11:30 and so on?