Shared experiences are key. If you've ever been on a tour with randos you'll know. You will form friendships with all kinds of people you never would have expected to back home.

I've made some very good friends since leaving university. The simplest thing to do is to start with something YOU enjoy. Food, sports, music, pottery, knitting, boardgames even coding (gasp but that's our work).

If you have a passion and you want to be there, and so do the other people - the odds are in your favour that you'll get along.