You use hotspots to navigate to a 360 that you want to add hotspots to and click the button.
1. Once you click the button, you can move the hotspot to where you want by clicking and dragging the image. Once the center blue is where you want the hot spot hit the set button. If you no longer want a hot spot click cancel.
2. Now that you have added the hot spot, you can edit it by clicking on it.
In this case, it would be the green box in the screenshot below. Once you click on the hotspot, it will bring up a menu on the right. You can change the hotspot type by clicking the type dropdown in the yellow box below. If you are unhappy with where the hot spot is, you can adjust it by changing the heading and pitch by clicking on the arrows next to the numbers in the heading and pitch. If you haven't put anything in, you can always hit the delete button at the top of the menu and start over.
Hotspot types - there are different hotspots you can add:
Info - with the info hotspot, you can enter a title, a still photo, and a description.
Video - the video hotspot is similar to the info, except instead of adding in a still photo, you put in a YouTube URL of the video you would like to incorporate.
URL - With the URL hot spot, you simply put the URL you want to link.
Audio - The audio hotspot allows you to upload audio in MP3 and OGG format.
Elevator up and down - The elevator hotspot simply allows you to link to another 360. You will need to enter the PanoID to do this.
How do you get a PanoID?
The easiest way is to navigate to a 360 you want to link in the custom builder and click the copy PanoID link on the image.
Another way to paste the Google Maps URL of a 360 in this tool is https://login.tourbuilder.com/#/tour/panoid/from/maps/url