This was a big sticking point for me and it's definitely not internalised yet. The biggest thing is timing, the longer you leave it the weirder it gets, shake hands place your hand on their back touch the side of their arm when you make a point ect but do it straight away and it will seem normal leave it too long and it's creepy. I also find that once I get started it's pretty easy to carry on, so kino with friends a lot as soon as I'm out.