GrapheneOS has two officially supported installation methods. You can either use the WebUSB-based installer recommended for most users or the command-line installation guide aimed at more technical users.
We strongly recommend using one of the official installation methods. Third party installation guides tend to be out-of-date and often contain misguided advice and errors.
If you have trouble with the installation process, ask for help on the official GrapheneOS chat channel. There are almost always people around willing to help with it. Before asking for help, make an attempt to follow the guide on your own and then ask for help with anything you get stuck on.
The command-line approach offers a way to install GrapheneOS without trusting our server infrastructure. This requires being on an OS with proper fastboot and OpenSSH packages along with understanding the process enough to avoid blindly trusting the instructions from our site. For most users, the web-based installation approach is no less secure and avoids needing any software beyond a browser with WebUSB support.