see turn over a new leaf.
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
Examples from the Web for new leaf
Historical Examples of new leaf
Over the exquisite forest of new-leaf trees the stars came out at length, and the guardians began to observe him.Fairfax and His Pride
Marie Van Vorst