Not fun.
For the parent or for the child.
Some suggestions -
Pre-tantrum;
1. Model self-control and patience yourself
2. Have a predictable pattern for most days
3. Make most of the decisions for the child
Mid-tantrum;
1. Do not give them an audience
2. Do not try and dialogue with them
3. Never give them what they are fussing for
Post-tantrum;
1. Administer a meaningful age-appropriate consequence
2. Role-play expected behaviour for next time
3. Gently and patiently teach obedience and self-control.