To join the VRChat service, a free to use virtual reality headset program that also works without a headset via keyboard and mouse, you must chose either of the following options.
Go to the main developer's website http://www.vrchat.net
Download the program
Install the program
Launch the program
Setup a free account in the program
Go to http://www.twvrc.com
Click on a Chaos Gate to enter that Root Town
Go to the store and search for VRChat
Alternatively go to this page http://store.steampowered.com/app/438100/VRChat/
Install the game to your Steam's library
Right click VRChat in your Steam library
Go to properties
Click "Set Launch Options"
Copy paste this information
Select Okay and Launch VRChat
Whichever option you choose, the VRChat client will be able to be played with any of the following options.
Keyboard and Mouse
Samsung Gear VR
Google Cardboard Box
If you have any further questions, please ask for support in our Discord chatroom server.