By setting Account Manager restrictions, users can then only access records they're the Account Manager of.
You'll need CRM Admin rights in order to follow the steps in this article
Step 1: Go to Settings Centre
Go to the Settings Centre by clicking on System Settings in the navigation menu. Once within the Settings Centre, search for 'Configure User' in the search bar then click on the 'Click to Configure' link.
Step 2: Choose User
Simply choose the CRM user that you wish to set Account Manager restrictions for by clicking on the associated pencil icon.
Step 3: Enabling Account Manager Restrictions
Once within the CRM user's settings, navigate to the 'Permissions' page and click 'Enable' for the Account Manager restrictions.