Daily affirmation Startup

LO is a crier, has been sees a baby. Now, at 3yrs old, waking up for daycare, most days is stressful with her crying and being stubborn. She won’t look herself in the mirror or won’t let me sing something to shift the mood. However, I want to start using affirmation in front of the mirror while I do her hair. How do I introduce it gently, in a way she’ll accept it?