also keep the original markdown docs :P~

docs/usage-overview.md

@@ -0,0 +1,56 @@
+Watchtower is itself packaged as a Docker container so installation is as simple as pulling the `containrrr/watchtower` image. If you are using ARM based architecture, pull the appropriate `containrrr/watchtower:armhf-<tag>` image from the [containrrr Docker Hub](https://hub.docker.com/r/containrrr/watchtower/tags/).
+
+Since the watchtower code needs to interact with the Docker API in order to monitor the running containers, you need to mount _/var/run/docker.sock_ into the container with the -v flag when you run it.
+
+Run the `watchtower` container with the following command:
+
+```bash
+docker run -d \
+  --name watchtower \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  containrrr/watchtower
+```
+
+If pulling images from private Docker registries, supply registry authentication credentials with the environment variables `REPO_USER` and `REPO_PASS`
+or by mounting the host's docker config file into the container (at the root of the container filesystem `/`).
+
+Passing environment variables:
+
+```bash
+docker run -d \
+  --name watchtower \
+  -e REPO_USER=username \
+  -e REPO_PASS=password \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  containrrr/watchtower container_to_watch --debug
+```
+
+Also check out [this Stack Overflow answer](https://stackoverflow.com/a/30494145/7872793) for more options on how to pass environment variables.
+
+Mounting the host's docker config file:
+
+```bash
+docker run -d \
+  --name watchtower \
+  -v /home/<user>/.docker/config.json:/config.json \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  containrrr/watchtower container_to_watch --debug
+```
+
+If you mount the config file as described above, be sure to also prepend the url for the registry when starting up your watched image (you can omit the https://). Here is a complete docker-compose.yml file that starts up a docker container from a private repo at dockerhub and monitors it with watchtower. Note the command argument changing the interval to 30s rather than the default 5 minutes.
+
+```json
+version: "3"
+services:
+  cavo:
+    image: index.docker.io/<org>/<image>:<tag>
+    ports:
+      - "443:3443"
+      - "80:3080"
+  watchtower:
+    image: containrrr/watchtower
+    volumes:
+      - /var/run/docker.sock:/var/run/docker.sock
+      - /root/.docker/config.json:/config.json
+    command: --interval 30
+```