From the main screen, go to Settings > User Management > Manage Roles. Once the Manage Roles screen opens, click on "Access Rights" located beside the Role that you would like to add, edit or remove access rights to.
Notice how with our example, we will be editing the "Day Manager" Role, therefore we will click on the "Access Rights" option located at the first column of the role.
After the "Access Rights" option has been open, you will be presented with 3 different tabs: Actions, Visibility and Privileges.
Actions: This is where actions are assigned to roles to view, edit, add or delete under different pages.
Visibility: This is where you can hide or make a feature visible to each role.
Privileges: This is where you will allow, restrict, ask for confirmation credentials for different features to each role.