Before you as an admin want to add a membership to a player, first make sure that the player exists in your admin player list.
If the player does not exist in your admin player list:
Click here to learn more about this topic
When the player exists in your admin player list:
Click on Players -> Player list
Click on the player
Go to the Memberships tab
Click Add membership
Select membership type, renewal cycle
Choose if the player has paid for it already or if its unpaid
If you choose Unpaid, the player is now able to pay for it inside of the mobile app.