I can tell you, on the other end of the spectrum from the last 2 posts, that it's hard to stifle
being affectionate in public if you really enjoy it, and it's not fair for one of you to be overwhelmed
nor is it fair for one of you to be completely cut off from cutesy things while there are people
around.
I am super affectionate and I hate feeling like I can't spontaneously kiss my girlfriend just
because we're in public. That would make me feel really bad, actually. So don't let anyone tell
you you're being selfish or "affection is meant for behind closed doors"-- sorry, that's not how
everyone works.
Luckily my girlfriend is very affectionate with me, too, regardless of where we are.
But we had to hide out relationship for a bit (queer issues) so for a year we had to be sly about
showing affection. We held hands under the table, I kissed her on the cheek when no one
was looking, and when we were sitting side by side I'd sometimes lean over onto her shoulder
for a second and quietly say, "I love you." There are definitely ways to be subtle about your
romance, while still meeting in the middle.
You'll probably have to just try to do so, and work out the kinks as you go. Just keep open lines
of communication in case you ever go just a bit too far for his comfort zone. Try to recognize what
he seems comfortable with doing, and stick to that.