Even though this is an old-ass thread, but the first thing I look forward to when seeing a woman naked for the first time is in seeing if her nude body matches up to what I expected when I only saw her clothed, but particularly in the full or at least partial pubic bush that she hopefully has. It is that anticipation in seeing the possible variations of hair, like amount, pattern and color for the first time that gives me an instant hard on. While I've been both surprised, like when the carpet matches the drapes or somewhat disappointed, such as when it was all hardwood and there was none, but it was always a moment to look forward to.
As far as what I want to physically do to her first would be to simply caress her, with maybe some light kisses, before actually getting into the hot & heavy stuff, though on many occasions I blew right past that point since in swinging it is usually all about getting down to the sex and some couples had a nonsensical "no kissing" rule.