Make new friends with others that have underdeveloped social skills and figure it out together.
Do things in a group in some activity that won't put the spotlight directly on you and where you can observe others.
Explore therapy where odds of rejection are pretty low since you're paying them for coaching.
I think noticing how children play is very instructive, but if you don't have good social awareness that could get you in trouble. Kids haven't internalized all the baggage you and I might have about social rejection and awkwardness yet. They just confidently say "hey I like your bracelets will you tell me what they mean to you?" and if it doesn't pan out this time they play with someone else. It's the social anxiety / awkwardness that usually makes people the most uncomfortable, not the atypical interactions. Kids don't have that at all.