1. Start off by going to the TCAdmin Control Panel and shutting down your server, then click on the 'Configuration Files' button.
2. Once you're in simply look for the 'serveradmin.xml' file and hit [ Text Editor ].
3. Once opened, you should find a config file similar to this -
Here you can go into further details of adjusting each permission level and also adding new commands, this will just explain the basics of giving yourself admin.
4. Look for this line - <!-- <admin steamID="76561198021925107" permission_level="0" /> --> - near the top of the section.
5. Remove the <!-- AND --> so you're left with just - <admin steamID="76561198021925107" permission_level="0" /> - this is an example of how it should look like -
6.Replace the steamID with your own ID, you can find your Steam64ID here - http://steamid.co/
7. Save the file and you should now have admin abilities!
NOTE: The file includes a detailed instruction guide near the top, so be sure to also read that if you're having difficulties.