This all reads quite basic. I find, breaking the ice is the hardest part. But even before that, the social norm that dedicates that ones should not bother strangers is the hardest to overcome.
It's probably blindingly obvious to others but the following rules have served me well.
1. Never approach a group that is evenly distributed around a circle. So if 2 people are opposite or 4 or a square don't engage. Do multiple loops until you find a group you can approach.
2. Have a good magic trick. I have a very nice one that involves a pack of playing cards and then involves a lot of eye contact while I "read your face" to work out the card.
I have found 99% respond yes to "would you like to see a magic trick?". It works equally well on CEOs as it does students.
That being said, if it works for you that’s great! Just pointing out that a yes doesn’t mean success in these situations
I think the better criticism, if we want to look for them, is that doing a magic trick only works because it is a novelty. If every interaction with someone new started with a magic trick it'd be even more bizarre than the social rituals we already have.