I avoid people. If it's really bad then I isolate myself from everything, perhaps try to sleep it off. I've also had this crazy long lasting suicidal project where I'll start searching on google maps endlessly for a nice place to end. Idk why but searching for a place to end really soothes me. That seems to discharge whatever it is that causes the manic mood. The crazy part is that usually I'm 1000000% dead set on ending. It isn't until the next day or whenever that I start give up on the idea of ending.