This article is from the Internet Personals: Advice for Gay Men FAQ, by Fred Young firstname.lastname@example.org and Dean Esmay email@example.com with numerous contributions by others.
I recommend picking a safe, neutral spot, and just sitting down
over coffee, or perhaps light dinner at a casual restaurant.
Emphasize that your first meeting will be for just that, meeting.
Don't expect much more than that you'll sit down, get used to
what the other person looks like, maybe have a bite to eat, then
In some regions, it may not be very comfortable to talk about
gay-specific matters in public. In such case, I still recommend to
meet in a safe public area - a museum, a park, or a restaurant with
secluded booths. Then, if it seems appropriate, move to a more
private location. Use Common Sense!
And if it doesn't work out, or the other person decides at the
last minute not to meet you, hey, that's okay! It happens to
practically everyone! And who on Earth said you're the perfect
someone for everyone you meet anyway? Who said that everyone you
meet is the perfect someone for you? At minimum, you should have
made a new friend this way; maybe more will develop, or maybe it
won't. Stay calm, don't expect much, but be open to whatever
might happen. And, enjoy your new friend!