Go to the fixtures tab, then select training option, along the top three options bar.
Click add training...
Or add friendly...
Confirm and then tell your squad. This will send them out a notification which encourages them to select their availability for your training session or friendlies.
You can then see your available players in the ‘squad tab’ of the friendly or training session.
Note: You cannot pick a team for a friendly or a training session. This is reserved for league/cup matches only.