The Actions tab allows you to filter places and perform bulk actions such as assigning representatives to more places at once. You can use Place assignments to limit what your representatives can see from their apps. If you want to do that, take a look at this article How to restrict reps to certain places.
1. The Place tab is located under the Activities tab. Click on it to enter.
2. Use filters to narrow down your list of Places. You can choose all by checking the Select all box or you can choose which places to select. When you make your selection, click on the Edit as pictured below.
2. When you click on Rep tab, a window with a list of your representatives will open so you have to check the ones you wish to assign to the selected places.
When you make your selection, click on the Apply changes
Result
After you've performed the steps described above, the selected reps will be assigned to their Places.