How do I create a segment of test users?

There are a number of options available:

If you can identify your users User IDs or Device IDs in App Data > User Profiles/Devices:

or have access to them from another source such as one of your backend systems. You can then create a test user segment with a list of User/Device ids:

This can be used in your campaign in the segmentation engine, select segments:

Then Segment:

And enter the name of your test segment:

A variation on this approach if you are not resolving devices to users is to edit the user ID to be identical across your test devices in your test group:

Find Devices and go to edit details:

Add a common User ID:

In the segmentation engine go to User Info  > ID and enter this common id:

Alternatively, if you are adding an ID from your external system to the platform when integrating, you can upload a CSV of the test users, using their user IDs from your own system, details here:

https://support.xtremepush.com/hc/en-us/articles/206034392-Add-a-segment-from-a-CSV-of-user-ids