Gentoo Guide @ Linux Guide:

Gentoo, another very customisable Linux distro. Like Arch and Nix OS, the installation process involves the command line and you doing all the configuration. For the Gentoo HandBook, Click Here

Install Medium:

1. AMD64
2. Alpha
3. HIPPA
4. MIPS
5. PPC
6. PPC64
7. Sparc
8. X86

For 64Bit Users please use the first medium. For others please look through the Gentoo Documentation.

Install Guide.

1. Download the select variant you wish to use. Click Here
2. Download Rufus or Bleana Etcher.
3. Select the ISO / OS Image you just downloaded in Rufus or Bleana Etcher.
4. Get a USB Drive and select it in Blean Etcher/Rufus and then flash it. The Program will do the rest.
5. Once done. Enter the BIOS of your PC/Laptop and edit the boot order so your PC/Laptop is booting from the USB Drive.
6. Once Booted, please follow the medium's respective installation guide. Linked above.