Planning and preparing is such an important part of what we do, and it really comes down to what works for the individual (sometimes within the frame of a school or states requirements).
I created a little freebie to share - a weekly and daily planner, featuring one of my hand drawn clip art pieces.
I have previously shared my elementary weekly planning pages. It is a simple and versatile template covering the main learning areas and includes a set of blank pages as well.
For those new to teaching Montessori (either in the home or classroom) there are some handy resources for scope and sequence aspects in following the child: