README.md: Add Gentoo installation documentation

Author: cova-fe

README.md

@@ -43,6 +43,7 @@ If you're a mere mortal like me and you're tired of hearing how powerful git is
   - [Solus Linux](#solus-linux)
   - [Ubuntu](#ubuntu)
   - [Funtoo Linux](#funtoo-linux)
+  - [Gentoo Linux](#gentoo-linux)
   - [FreeBSD](#freebsd)
   - [Conda](#conda)
   - [Go](#go)
@@ -172,6 +173,30 @@ Funtoo Linux has an autogenerated lazygit package in [dev-kit](https://github.co
 ```sh
 sudo emerge dev-vcs/lazygit
 ```
+### Gentoo Linux
+
+Lazygit is not (yet) in main Gentoo portage, however an ebuild is available in [cova overlay](https://github.com/cova-fe/cova-overlay/tree/main/dev-vcs/lazygit)
+
+You can either add the overlay to your system and install lazygit as usual:
+
+```sh
+sudo eselect repository enable cova
+sudo emaint sync -r cova
+sudo emerge dev-vcs/lazygit
+```
+
+Or you can download the ebuild and install it manually; please consider the example below just as a suggestion to be adapted to your system.
+
+```sh
+su
+LAZYGIT_VERSION="0.39.3" # Replace with the version you want from cova-overlay
+cd /usr/overlay/dev-vcs/ # Replace your overlay path
+mkdir lazygit
+cd lazygit
+curl -O https://raw.githubusercontent.com/cova-fe/cova-overlay/main/dev-vcs/lazygit/lazygit-${LAZYGIT_VERSION}.ebuild
+ebuild lazygit-${LAZYGIT_VERSION}.ebuild manifest
+emerge lazygit
+```
 
 ### FreeBSD