Make sure you attitude is right. The kids are not there to be merely tolerated for their antics. This is actually their domain. You have to be fully ready to accept them for what they are regardless of how unusual you think their behaviour might be. You have to go with the flow of life (which is not to say conform to it necessarily) but there is no value in isolating yourself from whatever is happening.
If there is an event or a big do, or something that a lot of people will be attending, go out of your way to try and make the necessary arrangements to make it possible for you to attend.
Join at least two clubs or socs, even if you never attend.
Interact with the kids, and not just on an academic level, and never ever patronise them. Don't be scared to make friends with a bunch of 18 year olds. You're at university. Who cares what anyone outside thinks?
It would help if you are fully prepared to laugh at yourself for your age. After all, you are the odd one out. There are no prizes for not adapting to technology. Moaning about having to text questions to the lecturer or if certain facilities are only app based will get you nowhere.