If your league plays a "shotgun" start, where everybody starts at the same time, you can set that up in the Tee Times section in administration. You'll set the starting time and starting holes for each group.
For each group in your league, set the tee off time to the same starting time. In this example, we start at 5:00pm:
To the right of each tee time you can set the starting hole for each group. For 9 hole leagues, you will set the starting hole for when you're playing the front, and when you're playing the back. For 18 hole leagues, you will only have one option to set for the group's starting hole. Choose the starting hole for each group from the drop down list for the appropriate side.
You can set up to two groups on each hole if so desired, by choosing an "A" or a "B" group, or you can just set 1 group on a hole. I don't recommend placing 2 groups on any par 3s, as that will only cause pace of play issues since only one group can be playing a par 3 at any one time (this is also why really big scrambles are notorious slow, they book too many people on the course at once!)
In this example, when our league is playing the front 9, I have two groups starting on hole 1, and two groups starting on hole 2. However, when we play the back 9, hole #11 is a par 3, so I only want one group starting on that hole, so I have two groups starting on 10, one group on 11, and the remaining group will start on hole #12