Coaches can assign and edit Player Numbers directly on their team's Roster. Coaches can access Rosters through the Team Page of the Coach Portal.
Instructions
Navigate to your Account Menu > Switch to Public View
Click Account
Click Coach Portal
Select a team name to view the Team Page
Scroll down to view the team Roster
Click the jersey icon next to a player to edit their number
Use the arrows to manually increase or decrease the number, or type a new Player Number
The new Player Number will update automatically