Update README.md

Author: marcusds

README.md

@@ -6,8 +6,19 @@ This is provided without warranty or support of any kind.
 
 ## Instructions
 
+### Automatic install
+
+* [Install HACS](https://www.hacs.xyz/docs/use/) if you don't already
+* Add a custom repo to HACS using [these instructions](https://www.hacs.xyz/docs/faq/custom_repositories/)
+* In the Repository field enter `marcusds/homeassistant-arp_ssh`
+* For the Type select `Integration`
+
+### Manual install
+
 Install by putting the contents of `custom_components` in your `config/custom_components` directory and then restarting Home Assistant.
 
+### Configuration
+
 Add to your Home Assistant configuration.yaml:
 ```
 device_tracker:
@@ -19,4 +30,4 @@ device_tracker:
 
 * host is the address of the device to login to
 * username is the username
-* password is a path to SSH key
+* password is a path to SSH key