I love this question - it's so fitting for me! I just finished my own first draft a few days ago and am still in celebration mode. *does another jig*
We'd just begun our vacation, and all I'd known heading into our trip was that I would work on the WIP. After my progress during the first day's drive, when I saw several sub-plots begin to wrap up, I said to myself, "I could potentially finish this tomorrow" - and I did! We were on the interstate somewhere in Georgia when I turned to my husband and said, in my best matter-of-fact tone, "I just finished it." He cheered, offering to take me anywhere I wanted for dinner. It was a grand gesture, but our family was so tired we merely descended upon a hotel and ordered pizza.
I quickly decided our Florida vacation would offer the best possible break from the manuscript, but plan to tackle edits and polishing when we return later this week.
Good luck to you, Wannabe! And make sure to let us know when you've officially finished.