To play Agario on a private server, follow these steps:
Find a reliable Agario private server: There are several Agario private servers available online. You can use search engines to find them.
Connect to the server: Once you find a server, you need to connect to it. To do this, you will need to enter the server's IP address in your browser's address bar. The server's IP address can usually be found on the server's website or in the server's forum.
Create a nickname: Once you are connected to the server, you will need to create a nickname for yourself. This nickname will be displayed in the game.
Start playing: Once you have created your nickname, you can start playing Agario on the private server.
Agario private servers usually have different game modes and features than the original game. Make sure to read the server rules and guidelines before playing.