Sometimes I name them for obvious traits--Biter was the cockerel that bit people regularly, Snowy was all white, Goldy was a gold-colored sexlink.
Often, one chicken will have a trait that suggests a name to me, and that starts a theme that I continue until I get tired of it.
A particular set of 4 cockerels got names:
Biter--the one that bit me
Beater--the one that looked most like him ("Biter" and "Beater" were weapons in the book The Hobbit.)
Maximus--the larger of the remaining two.
Minimus--the smaller of the remaining two.
Sumatra chicks looked kind of like pandas or penguins, so we ended up with Panda, Penguin, Piper, Pocket, Pudding (that's alphabetically from darkest to lightest--we had blacks and blues.) My daughters spent some time with the dictionary, figuring that set out.
Dark Cornish chicks became Beetle and Caterpillar, because of what the markings on their backs looked like when they were chicks.
White Laced Red Cornish chicks had different markings on their backs, so they became Colon and Semicolon. Then of course the bantams of the same kind became Period and Comma. We had a well-punctuated chicken yard that year
A different year, a White Laced Red Cornish became "Corn Flour"-- a pun on "cornish" and "cornflower," plus her "red" was pale like cornmeal. Her sister with darker red then became Rye Flour.
One day I was trying to catch a particular chick, and said "she's a nut." So I named her Hazel. The one with green legs became Pistachio and the smallest became Peanut--so of course others became Pecan, Almond, and Chestnut. Then I branched out a little with Mahogany (a tree but not a nut), and Clover (a plant related to a peanut, because they were the same breed of bantam).
I had two cockerels that looked alike, so I cut the tail feathers short on one as a way to tell them aso I could tell which was which. The one with the short tail became Bob (because I "bobbed" his tail), and the other became Fred because it just sounded good to me. A family member who likes Veggie Tales said the other should have been Larry, so that's what I named the next cockerel.
A silver duckwing Old English Game Bantam got called "Ducky" until we could tell gender-- because it was going to be either Donald or Daisy (like the cartoon characters.)