Personally, I focus a lot on comfort.
The place you CTB is the last place you'll ever be. You probably want it to be a place you're comfortable with, to make things at least a little bit more easier and peaceful for yourself. In terms of comfort only, I'd honestly do it in my bedroom if I could.
But obviously, there are other things to consider, mainly if other people can find you as you CTB. So for a lot of people their own homes aren't an option. There's also not wanting to burden the people around them with the discovery.
If you're nearby a beach or a mountain, and if you can find your own little secluded spot somewhere, I think that could work. Some sort of woods could work too, or maybe even a large park. If you cover up your windows and park somewhere secluded, I doubt you'll be found either. Getting a hotel room also works, but that also does leave the hotel staff having to find you eventually, which you'll have to consider.
If you're going somewhere new, try making sure that nobody actually does pass by that area frequently for whatever reason, no matter how secluded it may seem. Just being extra safe.
...and if you're going outside, pack some extra clothes. You don't want to be cold!!!
Hope you find your rest