If the server is configured as a public server, you can use the Steam server browser to join it:
- Open the Steam Client on your PC.
- In the menu bar at the top left, go to "View" → "Game Servers".
- Click the "Favorites" tab
- Click the "+" button
- Where it says "Domain name or IP and optional port" you need to type in/paste in your game server's "query info"
Query Info can be found on the home page of the game panel for your server. - Click "OK"
- Now your game server has been added to your Steam Server Browser Favorites, you can join it two ways:
- Right-click your server in the Steam Server Browser, then click "Connect to server"
OR
- Go in-game, open the game's server browser, click the "Favourites" tab, then click join/connect/etc.
If the server is configured as a private server, you will need to use IP direct connect to join it:
- In your gamepanel, home page, find "Connection Info" - make note and/or copy this info
- Open the game
- Click "Multiplayer"
- Click "IP Direct Connect"
- In the "IP Address" text field, enter the IP part of your connection info (the number that looks like 123.312.132.321)
- In the "Port" text field, enter the Port part of your connection info (the number after the : like 27015)
- If you have a server password, enter that in the relevant text field.
- Click "Connect"