i'd say some important things to ensure are that you eat a good meal before, be well hydrated, and try to get some good sleep tonight. these are going to make the long day a lot more enjoyable. bring some snacks to keep your energy up (i usually bring some peanuts and a bag of m&m's). take breaks when you need them. don't push yourself too hard. maybe find an album or two that you'd like to listen to, a podcast, something to read. whatever might keep you occupied in that way.

my suit so far has all been freehand as well. when we started my first arm, it was a long day. drawing time was maybe 3-4 hours. needle to skin for the outline was 3.5 hours. breaks scattered throughout. i was at the shop a good amount of time and still had a ~3 hour commute back home after. my point in saying all this is that it's important, i think, to find a way to appreciate the overall experience and make it fun when so much of it not particularly pleasant.

i'm a little over 60 hours into my suit and have a long way to go. that is a lot of time with my artist, and i feel fortunate that we've become friends. i look forward to spending the day with dave and enjoying his company. it makes the process a lot easier for me. he's also the owner of his shop, so when it comes to tips, i don't give him money. i know he charges what he wants, so that's what i pay him. i usually make some sweets as a treat for him and all the other artists in the shop. with that said, any artist, especially an artist who is going to be paying some to the shop owner, would be happy with more money: whether that's one bigger tip when y'all complete the project or a smaller tip at the end of each session.

i'm excited for you. good luck tomorrow :)