1. Book a last-minute getaway without doing much research into the hotel. All you really need to know is that there are en suite facilities, right?
2. Pack very lightly. You can probably wear the same clothes for most anything that comes up, right?
3. Arrive at the hotel, discover that it's a really, really nice hotel, like The Porches at Mass MoCA, and that they have a heated swimming pool with heated stone pavement surround(!) and a hot tub, and all of that water fun is available to guests every single hour of the day and night. But you have no swimsuit!
4. Quickly discard the idea of skinny-dipping. This is a family hotel!
5. Get directions to the discount chain store. Or, failing to do that, drive in ever larger circles around the perimeter of the town until you come upon such a store.
6. Run in (the sun's going down!) and locate the swimsuit rack, which is always kind of right in front, right?
7. Grab anything that's "your color," and don't worry too much about style or size.
8. Dash into the dressing room. Since there likely won't be an attendant, find any room that's open, despite fussy, discriminatory signage like "Men" or "Women."
9. If you can get into it, it's good enough. Again, the sun's about to go down!
10. Rush back to the hotel, change into suit without taking time to look into the mirror. Anyway, it's dark out now, so...
...slide into that hot tub and enjoy a soak. You haven't had time to fret about how you look in the suit, and you probably look just as good as anyone else in the pool area.