Here is Step 3 in “CALM”:

Label: Help them identify their emotions and hold them safely

It can be really hard for a young child to know what they’re feeling, particularly when in a heightened emotional place. Help them to understand their feelings and label them, without assuming. For instance, when my daughter is inconsolable I may ask her “Are you feeling sad or angry right now?” Giving a menu of a couple of emotions can be helpful so the child can hear some cue words that may help them emote what they are feeling. 

Then, whatever the child is feeling, even if they can’t label it, hold that emotion safely. This is not the time to give them a list of all the reasons they shouldn’t feel that way (honestly, that’s never helpful and is almost always invalidating.) Even if you have the impulse to help problem solve or offer some thoughtful reflection about their tantrum and what led to it, try to avoid doing that at this stage. Right now you are really just trying to convey, in words and/or in a loving hold, “these feelings are okay, you are safe, I am here with you.”  In this stage you are riding out the storm until it passes, without any agenda.