I guess that depends some on why your scared. You could read a book, take a walk, listen to music, take a hot bath. Or, you can just face what it us that's frightening you. Many things you can do to keep your mind occupied.
It tricks the mind into thinking that your body is okay. Because your body wouldn't eat if it were under duress. So, chew gum when you are scared or have to speak in front of a big group.
Prayer of thanks, praise and give ask for strength. If possible take a walk. Sit on your patio or balcony and watch everything. Write your fear down and face it.
You dont want to relax in a situation. Let your adrenaline and survival senses do their job
listen to music.