chore(docs): provide usage example

README.md

@@ -19,3 +19,37 @@ You can install the package via Composer:
 ```bash
 composer require krystal/katapult
 ```
+
+## Usage
+
+It will use PSR HTTP discovery to locate an imlpementation of the PSR ClientInterface.
+
+If you need control over this, you can call `setHttpClient` in `ClientFactory`.
+
+The usage sample below emits the IPv4 and IPv6 addresses for each VM in your Organization.
+
+```php
+use Krystal\Katapult\KatapultAPI\ClientFactory;
+
+$katapult = (new ClientFactory('your-katapult-api-token'))->create();
+
+$virtualMachines = $katapult->getOrganizationVirtualMachines([
+    'organization[id]' => 'your-katapult-org-id',
+])->getVirtualMachines();
+
+foreach ($virtualMachines as $virtualMachine) {
+    echo $virtualMachine->getHostname() . PHP_EOL;
+    foreach ($virtualMachine->getIpAddresses() as $ipAddress) {
+        $prefix = filter_var($ipAddress->getAddress(), FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) ? 'ipv4' : 'ipv6';
+        echo '  ' . $prefix . ': ' . $ipAddress->getAddress() . PHP_EOL;
+    }
+}
+```
+
+Output
+
+```
+example
+  ipv4: 93.184.216.34
+  ipv6: 2606:2800:220:1:248:1893:25c8:1946
+```