To teach phonics it is best to have a phonics book that contains a lot of rhyme and repetition, or you can use the Montessori way and make up words with sandpaper letters. The sandpaper letters have the advantage off adding feeling to the learning experience. 

A good phonics book will have lists of rhyming words like cat, mat, sat, hat, and bat. The accompanying passage will have sentences using all the rhyming words that make up a story. Even if the story doesn’t make complete sense it doesn’t matter, as you are getting your child to say similar sounding words. Anyway your child will not really understand the story, but that doesn’t matter. The main exercise of the story is to expose your child to as many rhyming words that sound the same, so your child can start to distinguish between different sounds.