Try not to look of it as boring, but think of it as freedom to do what you like. If you enjoy your job, think of other ways you can contribute. Take on new tasks or challenges. Your supervisor might appreciate the initiative.
If you don't like your job, then work on other personal projects. Reading, writing, anything else that's interesting that you can do at work. Be careul, though. It may look bad if people constantly see you "not working." Making your job look too easy might give some people the idea you're expendable. It sounds silly, but I will usually save my work for when other people can see me doing it.
There's also another side to having a supervisor who's never around. I (briefly) had a boss who never actually supervised me, and she consequently developed some very strange (and wrong) ideas about the way I work.
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I'm not autistic, although I do not consider myself neurotypical. I've been diagnosed with major depression and socially avoidant personality. Bonus: bipolar disorder.
~My soul must be iron, because my fear is naked.~