From manage.popforums.com, you need to create a management account with the link that says "create a new hosted account." A management account, or master user, is global to all of POP Forums, and is used to manage billing, themes and any settings that are not part of the core forum functionality. A forum administrator is specific to the forum, and allows you to set up categories and forums, delete user accounts, etc. These accounts have nothing to do with each other. On the "buy" page, there are fields asking you to specify the name, email and password of the admin user for the forum itself. You'll use those credentials to login to the forum once it is provisioned.
It may take a few minutes to provision your forum. Once it is ready, you'll see a link on the manage site that will lead you to the new forum, which will be empty.
As indicated above, a management account, or master user, is global to all of POP Forums, and is used to manage billing, themes and any settings that are not part of the core forum functionality. A forum administrator is specific to the forum, and allows you to set up categories and forums, delete user accounts, etc.
POP Forums at its core is a stand-alone open source project that a developer can stand up on her own, and once your forum is provisioned, it can be used as such using the admin account.
Login to your new forum. After you login, you'll see your name at the top, and a drop-down menu that includes a link to "POP Forums Administration." That will get you to the general settings. The drop-down there leads to a number of settings pages that you can review. You may want to add text to your terms of service here. On the email page, you can change the "from" email that system-generated emails come from, as well as a signature for those emails (maybe your forum title and a link). For the full documentation, go to administration settings.
The most important settings are the forums and categories. This is where you create and order your forums, and optionally group them under categories. You need at least one forum in order to start discussion. On the forum admin page, click "add forum," give it a name, then save. You can always edit the details later. By creating categories, you can group forums together.
Once other users have signed up, you can designate them as moderators or administrators. Moderators can edit and delete posts, as well as close, pin and delete topics. Moderators can enter the admin pages that you're currently exploring. To assign this role to users, go to the edit users page in the forum admin. Search for them, and click on the right result. Check boxes for "admin" or "moderator," then "save."
From your management list on manage.popforums.com, click the "manage" button next to the forum you want to customize. Click the "customize" tab at the top, then click "theme." Use the pull-down menu to choose a different color scheme. You can see samples of these themes at Bootswatch. You can also point to any Bootstrap v4.x based style sheet that you host on the web elsewhere by choosing "custom" from the drop down list, then entering the URL of the style sheet in the box that appears. Click "save." For more information, go to custom CSS (style).