Tips on surviving a 4-6 hour long tattoo session

Hello,

So I’m getting a large tattoo at the end of August. My tattoo artist said that it would take 1-2 hours to outline and 2-4 to color in. His minimum time is two hours and I’m kinda hoping to finish the entire tattoo on that day. Is that even humanly possible? What are some tips/advice on lasting that long. I think the longest tattoo I’ve ever gotten was an hour and a half.

Thank you!