Pre-teach your child what behavior you expect before a tantrum hits. Learn the triggers and address them with planning.
During a meltdown, try to:
1. Look at the child.
2. Talk calmly and softly about what they're doing.
3. Move them to a quieter place, if possible.
4. Help them regroup and redirect their focus, perhaps by singing the ABCs.
5. When the tantrum stops, reinforce with praise and pick up where you left off.