update.md in lono-4.0.3

- old
+ new
@@ -1,6 +1,33 @@
 ## Examples
 
+Let's say we make a simple change to a template, like changing the default InstanceType from `t2.small` to `t2.micro`.  Here's what happens when you run `lono cfn update`
+
+```sh
+lono cfn update ec2
+```
+
+The output should look similiar to this:
+
+<img src="/img/tutorials/ec2/cfn-update-instance-type.png" alt="Stack Update" class="doc-photo">
+
+Notice that before the update gets performed lono provides a preview of the changes that are about to take place. There are two types of "diffs" in the preview.
+
+1. Source code diff of the templates. This is generated by downloading the current CloudFormation template and comparing it with the locally generated one using `colordiff`.
+2. CloudFormation Change Set list of changes. This is generated using [AWS CloudFormation Change Set](https://medium.com/boltops/a-simple-introduction-to-cloudformation-part-4-change-sets-dry-run-mode-c14e41dfeab7) feature.
+
+You are prompted with an "Are you sure?" confirmation before lono continues.
+
+By default, the update command will display a preview of the stack changes before applying the update and prompt to check if you are sure.  If you want to bypass the are you sure prompt, use the `--sure` option.
+
+```
+lono cfn update ec2 --sure
+```
+
+## Conventions: template and param
+
+Lono follows some [coventions](http://lono.cloud/docs/conventions/) that helps keep the commands short.  We'll go through an example to explain:
+
 Provided that you are in a lono project and have a `my-stack` lono template definition.  To update a stack you can simply run:
 
   lono cfn update my-stack
 
 The above command will generate and use the template in `output/templates/my-stack.json` and parameters in `output/params/my-stack.txt`.  The template by convention defaults to the name of the stack.  In turn, the params by convention defaults to the name of the template.