From sweet girl to little dragon

What to do with a toddler puber

'No! I do. Do Zelluf. Mine!'
As the mother of a real toddler puber, these terms fly around my ears every day. But yes, how do you deal with that?
Enough time vs. little time
If we have the time, we let Kate try things for herself. She often comes to the conclusion that something is not working. And then she asks nicely if I want to help her. But when there isn't that much time, I'm going to help her right away… push. This often ends in an angry mood from at least one of us.
Wasted energy.
Because it is not faster and certainly not more fun.
Toddlers want is law
Going against the will of my toddler puber is also not always wise. She then changes from a sweet girl to a little dragon within two seconds. With some explanation and distraction, it often succeeds to change her back. But sometimes there are those days when, after a whole morning of conflict, I ask her:
"Would you please be a little bit nicer to me?" 
And when I get the answer: "I don't think so, Mommy." 
Then I can only do one thing… laugh very hard.