Forgive me if I'm going down the wrong path here but it sounds like you're looking for advice to make connections last beyond initial meetings, or even to socialise with people you see often but only in groups.

If that's the case then I'd encourage you to think consciously before and during events about being prepared to ask people about making plans.

Seize on common interests and think of what can be done after the event, and make a plan for it during the event. If someone mentions a favourite bar/cafe/restaurant, say you'd love to go. Same goes for movies, business talks, exhibitions, etc.

If your focus is more work related then something small like organising a coffee meetup with a set purpose is great. Gather freelancers to talk finances, or project management, or client relations. Gather people in your role together to exchange stories over a drink.

There's even a chance that if you float the idea or hint at it, someone else might volunteer to organise - you'd just need to turn up (although really some of these suggestions don't require much more than turning up either - just a time and a place!).