M.C.
Teach him letter and number recognition using what you already have or flash cards. Clap out syllables. Try to start with writing his letters also. Kindergarten starts with sight words so try to get him to read small words like: an, the, like, cat... Show him that the beginning of sentences start with the capital letters and ends with a period. Also rhyming is pretty big in Kindergarten.
My son started Kindergarten this year and had none of this training. Suprisingly enough he has picked it up pretty quick but any little jumpstart is helpful.