Adding better instructions.

README.md

@@ -10,6 +10,36 @@ OpenMG is a GTK4 + Libadwaita manga reader written in C which uses `readmng` as
 
 ## Installing the app.
 
+These are the installation methods supported currently.
+
+### Flatpak
+
+Download from https://gitea.sergiotarxz.freemyip.com/sergiotarxz/mangareader/releases the latest `openmg-x86_64-(version).flatpak` and run:
+
+```shell
+flatpak install openmg-x86_64-(version).flatpak
+```
+
+Beware that not being in Flathub yet you will have to come here again
+to get updates.
+
+### Gentoo
+
+```shell
+sudo eselect repository enable sergiotarxz
+echo 'app-misc/openmg ~amd64' | sudo tee -a /etc/portage/package.accept_keywords/zz-autounmask
+sudo emerge -a openmg --autounmask
+```
+
+If the installation ask you for a package masked for ~amd64 you can run
+`sudo etc-update`, upgrade the `package.accept_keywords` config file
+and try again the latest command of the installation instructions.
+
+
+## Build from source
+
+### Flatpak
+
 First fine tune the options in `me.sergiotarxz.openmg.json` for
 meson you want to have, for example preview images, complete list is
 on `meson_options.txt`
@@ -22,12 +52,28 @@ flatpak-builder --install --user build me.sergiotarxz.openmg.json me.sergiotarxz
 
 ```
 
+### Native
+
+```shell
+meson build
+meson compile -C build
+sudo meson install -C build
+```
+
 ## Running the app
 
+If using flatpak:
+
 ```shell
 flatpak run me.sergiotarxz.openmg
 ```
 
+If native installated:
+
+```shell
+openmg
+```
+
 ## Donations welcome:
 
 btc: `bc1q0apxdedrm5vjn3zr0hxswnruk2x2uecwqrusmj`