Follow this blog to setup, deploy and test LAMBDA.

• Go to Services > Lambda > Create a New Function

• Select ‘Author from Scratch’ and provide basic information for the function.
  Default execution role can be left as it is.
  Hit Create Function

  

• After creating the function,
  Update the Code in the Code source section, Hit the Deploy button to update your code.
  Monitor window can be opened in a new tab for CloudWatchLogs.

  

• To TEST the function, click on Test then set up a test event.
  Event Data should provide parameters to your function if any in a JSON object format. If none, it should be an empty JSON object.

  

• After Test Event setup, we can start with Testing our Lambda.
  Hit the Test Button.
  You will see execution logs.

• Execution logs can also be accessed using CloudWatchLog.

  

  There you go, you have your LAMBDA ready for action.