Any have a SAM Local tutorial for custom authorizer in Lambda

I’m setting up a proof of concept Hello World page using API Gateway, Lambda, and SAM Local to do all of the configuration.

Been following this tutorial: Secure AWS API Gateway Endpoints Using Custom Authorizers

The problem is that the tutorial wants to do things in a certain order, for a manual setup via GUI. Some of the steps are redundant and out of order because SAM sets up all of the IAM and roles etc for you. This makes it a tad hard to follow the tutorial, for someone who is relatively new to the Lambda.

Has anyone set up the custom authorizer this way yet?

Thanks.