If you are teaching your child to read, and you wonder what letters to begin with, choose the 16 consonants that almost always make the same sound at the beginning of English words. Those letters are b, d, f, h, j, k, l, m, n, p, qu, r, t, v, x, and z.
Why these 16? These sound-letter pairings follow one-to-one logic. A d always sounds like a d when it begins a word. An r always sounds like an r when it begins a word. Later your child will learn that certain letters can represent more than one sound (all the vowels, for example) and that certain sounds can be represented by more than one letter (the z sound can be represented by z and s, for example). That can be confusing.
But for now, as your child learns to read, sticking to one-to-one relationships gives your child confidence. An m always sounds like an m. A k always sounds like a k.
Start with sounds that have meaning to children. If your child’s name is Marco, start by teaching the letter sound m, and tape Marco’s photo on an Mm card to hang on the refrigerator. If your dog’s name is Bandit, tape Bandit’s picture to a Bb card. However, don’t use pictures of words beginning with blended sounds (br as in Brian) or digraphs (sh as in Shelly).