Meeting a couple for drinks. What’s your line to see if they are interested?

We are meeting a couple for drinks this Saturday. We usually meet couples at a club or takeover. It’s been a long time since we’ve met another couple this way.
I’m sure we will have a hand signal or something between my wife and I if it’s a hard pass. And one for a hell yes too.
I’m curious to know how the conversation gets to the “wanna do it” part without it being awkward. Is it a vibe thing or do you have a standard way of steering the conversation if things are going well?
At clubs and takeovers things are more upfront since everyone is there for the same reason. This feels like it could be a bit of a delicate dance and I would prefer if things don’t get awkward.
Any tips or advice is appreciated.