Accept the things you can’t change, if you can or want to change, do it.
blow up your favorite cheerful song and sing at the peak of your lungs, dancing as you go.
Go for a run, a nice long run. Run until you feel good. At very least you will tired enough that the feelings will seem less major.
Call someone you love, just hearing their voice can make your day better.
Smile stranger it will make both smile.
Send an anonymous compliment.
Write down everything you don’t like about yourself and burn it.
Watch your favorite movie.
Trust yourself.