Update README

Author: simonrw

README.md

@@ -1,3 +1,23 @@
 # LocalStack Kubernetes Operator
 
-WIP
+## Requirements
+
+The LocalStack operator requires a LocalStack [auth token](https://docs.localstack.cloud/aws/getting-started/auth-token/) to authorize the use of the operator.
+
+## Installation
+
+You can use `kubectl` to install the LocalStack Operator into your cluster:
+
+```bash
+# latest version
+kubectl apply -f https://github.com/localstack/localstack-operator-public/releases/latest/download/controller.yaml
+
+# or specific version, e.g. v0.3.3
+kubectl apply -f https://github.com/localstack/localstack-operator-public/releases/v0.3.3/download/controller.yaml
+```
+
+## CRD definition
+
+The operator includes a `LocalStack` CRD which defines your LocalStack instance.
+
+Details TBD