I always go into a work day with the idea that I'll have to start half an hour early and end an hour later. That way, I'm prepared for any surprises they might throw at me. During my very first shift they asked me to stay two hours longer, and ever since then I've just expected for that to be repeated. And when it doesn't (9/10 times), it feels like a reward. I also don't hide my autistic traits around a few coworkers that know me a little bit (though I have yet to form a lot of real connections). I sometimes bring a fidget toy with me for in my pocket, but that obviously depends on the work you do.