How would Maya define a great teacher? What advice would she give to a new teacher?

Maya would probably define a good teacher as one who is accessible, attentive, and inspirational. 
Based on the story, Maya would probably consider Mrs. Bertha Flowers a phenomenal teacher. The older woman sets a good example in both conduct and speech. Mrs. Flowers also treats everyone she meets with respect. Maya tells us that Mrs. Flowers' smile is both "graceful" and "inclusively benign." The single greatest quality Mrs. Flowers has is her ability to make others feel comfortable in her presence.
Mrs. Flowers' attention to Maya facilitates the latter's emotional healing. In the older lady's presence, Maya feels accepted, valued, and trusted. In the book, Mrs. Flowers invites Maya to her home. There, she shares homemade cookies and lemonade with Maya and then reads to the young girl from A Tale of Two Cities.
Before Maya leaves, Mrs. Flowers gives her a book of poems to take home. The older lady tells Maya to memorize one poem and to recite it to her the next time she visits. Mrs. Flowers' attention brings Maya out of her shell.
If she had words of advice to give to a new teacher, Maya would likely tell him/her to be as caring, accessible, and accepting as Mrs. Flowers.