Allow Members to Create Their Own User Account

Users can create their own Drupal user account when signing up for a specific membership. Combining this with the built-in CiviMember Roles Sync feature will allow you to assign certain access to users upon signing up and paying for their membership. Here are the steps:

1. Create a Drupal User Role for that membership type (/admin/user/roles).
2. Assign it the permissions you want that membership type to have on your site (/admin/user/permissions)
3. Enable CiviMember Roles Sync in the Drupal Modules section.
4. Configure it by adding a new Association Rule that connects your CiviMember type to the Drupal role you just made. (admin/settings/civicrm_member_roles)
5. Go to Administer CiviCRM => CiviCRM Profiles.
6. Select Settings for the profile that you're using for your membership.
7. Scroll to the bottom and click Advanced Settings.
8. In the "Drupal user account registration option?" section, select "User account required".
9. In the Drupal User Settings, select "Visitors can create accounts and no administrator approval is required." and check off the "Require e-mail verification when a visitor creates an account" box.

Now when you view the live membership signup page while logged out, you should see an option for users to pick their username. Their password will be generated and sent to them via e-mail. After they complete their membership, they will be given the appropriate access you've provided in the Drupal Permissions.