How to play
In this tutorial, I will show you how to connect and play to other people's Runescape private servers. I assume that you have Java installed. If you don't, follow the installing java tutorial.
In order to play on other people's servers, you first need a client. Many different people publish their own clients, but most of them differ only slightly from the basic, unedited client. The mainstream client used today is called "MoparScape". It can be found here. In order to play using that client, you will need the Java plugin for your browser, which should have automatically been installed when you installed Java.
Once you have found the client, you need to find a server to play on. I would suggest visiting the server status page and looking for servers with a lot of votes. Each vote represents a person who liked that server. So, if you pick a server with a lot of votes, that generally means it has lots of good, original content and lots of players. Make sure that the server has a green bar next to it, meaning that the server is currently running and accessible. Sometimes, you will need to try other servers if the server you are on has too much lag. This is caused by a number of things, such as a slow Internet connection, or the server being hosted very far away from where you live. You can click on the server's IP address on the status page to bring up more information, such as its location.
Now that you have the server that you want, you can go ahead and log in. Press the 'Log in' button on your client. In some clients, this may be slightly different -- 'Play', for instance. You may now enter your username, password, and the server's IP address. Generally, you don't have to register before playing. You simple enter your desired username and password at the log in screen. However, if it says something like 'Invalid Username or Password', then you may need to register. The server's website can usually be reached by simple typing in the IP address of that server into your browser. If this works, you are now playing a private server. If it doesn't, you may need to try another server.