You can go to the Manage Your Account area of your database to perform a lot of the customization that is possible with your database. To access, click Manage Your Account from the menu under your name in your Top Right Menu bar:

You'll then see the below:

Below are links to working with all of the options you see here:
Preferences:
Change Site Preferences
Manage Integrations
Manage Team Notices
Manage Web Links
Email Management:
Manage Broadcast Emails
Manage Templates:
Automation Templates
Custom Export Templates
Activity Templates
Email Templates
Mail Merge Templates
Note Templates
Workflow Templates
Manage Files:
Downloads
Admins Only (these options are only available to admin users of the database):
Database Backups
Manage Database Lists
Manage Database Users & Teams
Membership Options
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