If it's another couple we generally meet up for dinner/drinks, or in the summer they come up to our place up north and camp with us so then we hang out by the campfire, cook, eat, go hiking, trail riding, etc.
If it's with a girlfriend we usually just go to each other's house, hangout together over coffee/something baked, chat, maybe watch a movie, sit outdoors in the summer, or we make a lunch date.