Children typically learn to rhyme before they ever read. Rhyming is an important precursor to reading. Play rhyming games and even reading nursery rhymes is beneficial. Talk about the rhyming words. Rhyming words sound the same at the end of words. Talk about how some rhyming words have similar endings (i.e. Jill and Hill). While other rhyming words sound the same but are spelt differently (i.e. In the nursery rhyme, Twinkle, Twinkle, the words, 'high' and 'sky' rhyme but their spelling patterns are different).
Aside from children knowing the letters and sounds in the alphabet, they should learn vowel sounds, and blends.
We teach children to listen for the sounds in words. Saying a word aloud and stretching out each sound allows children to listen for the sounds. Sometimes we like to forget about the letters and just focus on the sounds they hear!
See the link below for more fun with sounds!