Add step by step guide to walk through a fresh os

for linux installation.

Guides/install-linux.md

@@ -0,0 +1,58 @@
+# Configure a fresh linux installation
+
+## Install basic programs
+
+Install `git` and `fish`
+
+## Change default user
+### Add
+
+```sh
+sudo adduser jovian
+sudo usermod -aG sudo jovian
+```
+
+### Delete default user
+
+```sh
+raspi-config # boot > cli > not autologin
+reboot
+sudo userdel -r pi
+```
+
+## Clone configuration repository
+
+[From Gogs](https://gogs.jovian-hersemeule.eu/DricomDragon/JovianLinux)
+
+## Set up your tools
+
+By executing scripts from _Install_ folder.
+
+## Change hostname
+sudoedit `/etc/hostname`
+
+## Set up SSH
+
+### Add id key
+
+```sh
+vim .ssh/authorizedkeys
+```
+Test if working.
+
+### Remove password authentication
+
+```sh
+sudoedit /etc/ssh/sshd_config
+```
+
+## Desktop installation
+
+### Disable package update
+sudoedit /etc/apt/apt.conf.d/10periodic
+APT::Periodic::Update-Package-Lists "1";
+APT::Periodic::Update-Package-Lists "0";
+
+### Copy dot folders
+
+Like _.thunderbird_, _.mozilla_, _.ssh_