How do I enter a mega backdoor Roth IRA conversion?

Context: I did mega backdoor roth conversion last year (i.e. made after-tax money in 401k contribution and 

requested my 401(k) provider to automatically make an in-service distribution of my after-tax contributions into your Roth 401k every month). 

 

Question: I got 1099-R form from my broker (fidelity). Is there a step by step guide for mega backdoor conversion just like there is a step by step guide for backdoor conversion?

 

Once i enter the mega backdoor Roth IRA conversion, what should i check in Form 1040 to ensure i entered things correctly?