Added helm command and managed prefix list info (#63)

* Added helm command and managed prefix list info

* Fixed small goof

Author: chrisnegus

docs/how-it-works.md

@@ -29,8 +29,13 @@ Run through them again for a second cluster to use with the extended example sho
    ```bash
    eksctl create cluster --name <my-cluster> --region us-west-2
    ```
-1. Configure security group: To receive traffic from the VPC Lattice fleet, you must set up security groups so that they allow all Pods communicating with VPC Lattice to allow traffic on all ports from the 169.254.171.0/24 address range. See [Control traffic to resources using security groups](https://docs.aws.amazon.com/vpc/latest/userguide/VPC_SecurityGroups.html) for details.
-
+1. Configure security group: To receive traffic from the VPC Lattice fleet, you must set up security groups so that they allow all Pods communicating with VPC Lattice to allow traffic on all ports from the 169.254.171.0/24 address range. See [Control traffic to resources using security groups](https://docs.aws.amazon.com/vpc/latest/userguide/VPC_SecurityGroups.html) for details. You can use the following managed prefix to provide the values:
+   ```bash
+   aws ec2 get-managed-prefix-list-entries --region us-west-2 --prefix-list-id pl-0721453c7ac4ec009
+   ```
+   ```
+   ENTRIES 169.254.171.0/24
+   ```
 1. Create an IAM OIDC provider: See [Creating an IAM OIDC provider for your cluster](https://docs.aws.amazon.com/eks/latest/userguide/enable-iam-roles-for-service-accounts.html) for details.
    ```bash
    eksctl utils associate-iam-oidc-provider --cluster <my-cluster> --approve
@@ -78,10 +83,22 @@ Run through them again for a second cluster to use with the extended example sho
       --approve
    ```
 
-1. Run the following to deploy the controller:
+1. Run either `kubectl` or `helm` to deploy the controller:
+
    ```bash
    kubectl apply -f examples/deploy-v0.0.1.yaml
    ```
+   or
+
+   ```bash
+   # login to ECR
+   aws ecr-public get-login-password --region us-east-1 | helm registry login --username AWS --password-stdin public.ecr.aws
+   # Run helm with either install or upgrade
+   helm install gateway-api-controller \
+      oci://public.ecr.aws/aws-application-networking-k8s/aws-gateway-controller-chart\
+      --version=v0.0.2 \
+      --set=aws.region=us-west-2 --set=serviceAccount.create=false --namespace system
+   ```
 
 1. Create the amazon-vpc-lattice GatewayClass:
    ```bash