Read aloud to your child from the time he is an infant. This will introduce him to the sounds that words make. It will inspire imagination and increase the child's interest in books.
Go through the alphabet for a few weeks with your child. After he memorizes the alphabet, say each letter, make the sound and then create a word with the letter. Allow the child to then say the letter, make the sound and then make a word.
Write three-letter words in a column from the top to bottom of a blank piece of paper. Make another column beside it, this time consisting of two-letter words. Have the child read each word from the column. He will likely need help sounding out each letter as he reads. Have him practice the words each day until he is fluent.
Give your child books to read. Turn off the TV and read a book yourself. Your actions can inspire your child to start reading.
Introduce your child to more advanced books as he becomes a more proficient reader. Read with your child and ask him to read aloud to you, so you can determine the level he is reading.