Update INSTALLATION.md

Author: mdgaziur

INSTALLATION.md

@@ -17,7 +17,22 @@
 - Copy `css/style.css` to `/opt/findex`
 - Copy `target/release/findex` to `/usr/bin/findex`
 
+### If you have systemd
+- Copy `findex.service`, `findex-restarter.service` and `findex-restarter.path` to `/etc/systemd/user/`
+- Run `systemctl --user enable findex.service`
+- Run `systemctl --user enable findex-restarter.path`
+
+### If you don't have systemd
+- Add Findex to startup applications
+
+Unfortunately Findex can't restart automatically when configs are changed unless you are using systemd. That's a future plan. Till then,
+you'll have to restart it manually.
+
 ## Installation from AUR
 
 From repo: `findex-git`   
 Prebuilt: `findex-bin`
+
+If you are using systemd, run the following commands:
+- `systemctl --user enable findex.service`
+- `systemctl --user enable findex-restarter.path`