Updated docs

README.md

@@ -1,27 +1,40 @@
 # LambCI ECS cluster and Docker image
 
 More documentation should be coming soon, but to get up and running quickly,
-launch the `cluster.template` file in CloudFormation and give your stack a name like `lambci-ecs`
+launch the `cluster.template` file in CloudFormation and give your stack a name like `lambci-ecs`.
 
 (You should have already created a LambCI stack as documented at https://github.com/lambci/lambci)
 
 This will create an auto-scaling group and an ECS cluster and task definition,
 which you can find in the AWS console from `Services > EC2 Container Service`
 
+LambCI-ECS will look for a `Dockerfile.test` is in the root of the repository. This is where you put your test/build instructions.
+
 ## LambCI configuration
 
 You'll need to give the Lambda function in your LambCI stack access to run the task, so will need add to IAM
 permissions something like this:
 
 ```json
 {
-  "Effect": "Allow",
-  "Action": "ecs:RunTask",
-  "Resource": "arn:aws:ecs:*:*:task-definition/lambci-ecs-BuildTask-1PVABCDEFKFT"
+  "PolicyName": "LambCIECS",
+  "PolicyDocument": {
+    "Statement": {
+      "Effect": "Allow",
+      "Action": "ecs:RunTask",
+      "Resource": "arn:aws:ecs:*:*:task-definition/lambci-ecs-BuildTask-1PVABCDEFKFT"
+    }
+  }
 }
 ```
 
-Where you replace the resource with the name of the ECS task definition created in your `lambci-ecs` stack.
+This block should be added as part of the `LambdaExecution > Properties > Policies` section of the `lambci` template.
+
+Replace the `Resource` value with the name of the ECS task definition created in your `lambci-ecs` stack.
+
+![Example resource location](http://i.imgur.com/3U7NHQr.png)
+
+## Project configuration
 
 Then in the project you want to build using ECS, you'll need to ensure the following LambCI config settings are given:
 
@@ -34,6 +47,8 @@ Then in the project you want to build using ECS, you'll need to ensure the follo
 }
 ```
 
-(replacing with the actual names of your cluster and task)
+(replacing with the actual names of your ECS cluster and task)
+
+![Example cluster and task location](http://i.imgur.com/DKgcdBU.png)
 
 These are normal LambCI config settings which you can set in your `.lambci.js[on]` file or in the config DB.