Steps
Open the board from which you want to remove a collaborator
Click the "Share" button in the top-right corner
Locate the collaborator you want to remove from the list
Click the Right Chevron menu next to their name or their role
Select "Remove" from the dropdown
Confirm the removal action when prompted
The collaborator will no longer have access to the board
Notes
Removing access is immediate and permanent
The removed collaborator will receive a notification
You can re-invite them later if needed
Owners and Admins can only be removed by someone with higher-level permissions