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