In Montessori education letters are not introduced in their order within the alphabet. They are introduced in an order that allows the child to make many words with the letters that s/he has learned. You can read more about it at Deb's blog Living Montessori Now.
There are variations among Montessorians; I decided to use the order Tim Seldin's order. He is the writer of How to Raise an Amazing Child and this book is a great introduction to the Montessori education.
First set: c m a t
Second set: s r i p
Third set: b f o g
Fourth set: h j u l
Fifth set: d w e n
Sixth set: k q v x y z
I enjoyed preparing the first set. I simply sourced some small toys/objects from around the house and put them in a box.
C is for CarCatCakeCup
M is for MarbleMagnetMouseMedal
A is forAppleAlienAirplane
I put the boxes on the shelf and when Derin shows interest, we take a box. Sound the letter, trace the the sandpaper letters which he LOVES and say the name of each object.
I am planning to find more objects but if I can't find them I am planning to use pictures. If you'd like to prepare alphabet boxes but don't have sandpaper letters,you can use foam or magnetic letters,stickers,whatever is easy for you.