Choices. Lots of choices.
Exactly two, offered on everything you don’t care about.
“Would you like your left sock on first, or your right?” (you are deciding the socks are going ON, but your child gets to choose which order they go on)
“Would you like to carry your coat or wear it?” (you are deciding that the coat is coming with, but the child decides how)
“Would you like to empty the dishwasher or walk the dog?” (you are deciding that one of these tasks needs doing, the child gets to decide which one they will do)
“Which would you like first: your bedtime story or brush your teeth?” (you are deciding that both need doing, but the child decides the order)
Etc.
Instead of deciding things you don’t care about because you are in a hurry or whatever, let your child decide. Then when things you care about come up, you’ve built enough cooperation credit (that’s how I think of it) that you can just say to do this or that. It’s surprising how effectively it works.
The two choices should be things where it really doesn’t matter much which is chosen, and they should be kind on the same level of desirability to the kid.
So you wouldn’t offer “Would you like to have a snack or do your homework first?” (I mean, duh…plus you’re setting yourself for a battle when it’s time to do the homework.). This one might be more like “Would you like hummus and chips or some pizza bites for a snack to have while you do your homework?” (Remember, offer two choices, NOT “What would you like for a snack before you do your homework?” — this is too open ended and will likely end up in an argument about what is an appropriate snack.)
It takes practice to work this “hack”, but it never fails to surprise me when I get more cooperation than if I just say how I want things to go.
I learned to use this trick with my daughter, who *hates* to be told what to do. It saved my sanity when she was little.