Alliteration
Alliteration is like rhyme, only backwards. In other words, the beginning
of two (or more) words share the same sound. Alliteration is more
forgiving than rhyme, however. Simply getting the same initial sound is all
you need do – no need to match the entire final syllable.
Try inner alliteration, too (its actual name is “internal rhyme” if you
match a sound or syllable on the inside of a word instead of the beginning
or end). A hint of such poetic elements adds a pleasant touch to your
writing.
Too much alliteration, however, is like Tammy Fae Baker (if you’re too
young to know who this is, picture a woman with half an inch of makeup
applied to her face). It begins to sound like a joke and distracts from the
writing’s ideas.
At first, a little alliteration is a lot like a lollipop. But soon, the
sweetness gets so super saturated that somebody’s senses will get overstimulated
and stop savoring the experience. Get the idea?
And yes, it’s not the letter that matters, it’s the sound. K, C, and Q can
all work together, as can S, C and X.