[HaNdFisH]

1-3 units

Use of these varies depending on army composition and amount of dropping etc going on, most of the time 3 isnt used

4- unit production, for terran this is barracks/factories/starports
use tab to go between them
5- CC's/orbitals/planatarys for SCV production/mule/scan

I'm used to heavy tab use from wc3 (had similar control group setup there), so these are fairly natural for me. Use similar groups for the other races too, ie 4 = hatches, 5 = queens.