Exposure to handwriting in preschool will greatly help your students in Kindergarten.
I teach a class of 5 year old preschoolers who just missed the cut off date or whose parents have decided to give them another year before kindergarten for various reasons. Your method to teaching handwriting will greatly depend on your age group. Mine are old enough to have the fine motor skills needed to do this. Yours may not be.
Each week my preschoolers practice writing their name (first name the first half of the year and last name the second half of the year). They also practice writing the letter we are studying that week (this week I am teaching G is for Groundhogs, so they are practicing the letter Gg). Depending on the week we may also do the number of the week.
I print one copy of the letter sheet and number sheet and laminate them. I stick them in a binder and have my preschoolers use an overhead projector marker to practice their letters, numbers and names.
It works like a charm. In no time at all they are writing. These little ones will be ready for kindergarten in no time!