Something I discovered, that may not apply to everyone, is that sometimes for me there is a sensory component to it, where loud sounds, etc will increase my irritability. I realized I could use this to my advantage and put on really relaxing music or nature sounds like rain and this can help lower that irritability. Also, closing my eyes and taking deep breaths until the irritability passes a bit helps.

I also definitely agree with the exercise, especially if it's something like a hike out in nature.

Sometimes a shower can help, too.

Also avoiding things like caffeine that exacerbate it and eating healthy to keep my blood sugar stable.