Install Active Directory Domain Services

These instructions were written for Server 2008 R2, however they are likely very similar on other versions.

1. Set your server network adapter's DNS server to 127.0.0.1
2. Open the Server Manager (if not already open), click Roles then click Add Roles
3. Select Active Directory Domain Services, then install. Click Close this wizard and launch the Active Directory Domain Services Installation Wizard
4. Select Create a new domain in a new forest
5. Choose an FQDN for your domain
6. Select the Forest Functional Level (in most cases it's likely okay to select the highest supported unless you're planning on using older OSes as domain controllers)
7. Keep the default additional options (i.e. you should install the DNS server role)
8. Set your folders for database, logs, and SYSVOL (usually you can just keep them on your bootdrive)
9. Set a Directory Services Restore Mode password (should be different from your Administrator password!)
10. Review the summary and make sure everything looks good
11. Click next and let dcpromo do its thing, once its done you should be able to log into the domain Administrator account with whatever your local Administrator account's password was

Some quirks to keep in mind:

• For optimal performance, you should have at least two domain controllers, however this only really works if you have two physical servers to run them on (and it's not all that necessary anyways, you'll just have longer boot times on the DC if you don't have multiple)
• You cannot log into local accounts on a domain controller, so don't make any extra aside from the Administrator account before installing
• Most Microsoft servers that aren't built in roles will NOT run from a domain controller!