You can add a floor plan by clicking on Locations under the Setup category in the navigation. Click on the Maps tab and then click New Map.
Give your New Map a nap and upload an image of the floor plan and click Create.
Now click on Assign Rooms.
You can click on the location icon for each of the rooms available and drop it in the correct room.
When done click Save.
Now that your map is configured users can go to your app and click on the hamburger to find the option for Locate me now. Click this and it will show you what Session or Room is near you.