Some advice for naming characters…
Be aware of history, ethnicity and culture
The names you chose should be appropriate for the time and place of your book. Look up names of that time period, culture or background online and choose popular names for boys and girls.
If you are writing fantasy look at names for that mythos. For example elves often take Celtic names, dwarves tend to have Germanic names. You could follow this pattern – or choose to intentionally defy it.
Science fiction names could be evolutions of current names or the result of a far future society.
Don’t harvest other “ethnic” or “exotic” names without considering the character who will wear the name.
Don’t choose names that all belong with the same letter
In my VOID trilogy there are characters named Raven and Rachel and Revenge and Robin. Others are named Allie, Alaric and Avalon. Don’t make this mistake. Choose names around and about the alphabet so readers won’t be confused and your pages won’t be full of capital letters so it looks as though the novel is an episode of Sesame Street brought to you by the letters R and A.
Make the names meaningful and/or mysterious
You can search for names online by meaning. Use that to pick a name with resonance and meaning for that character’s role in the plot.
In Waking Dream my primary characters are Poppy who explains her own name as not meaning the red poppy but the white opium poppy of drugged dreams; Bethany whose father is dead and whose name means “House of Affliction” and Rivalaun, a Celtic name for a slightly fey character.
In Ghost of a Chance the ghostly protagonist with a quest to find her own murderer is named Evangeline. In Bad Blood the characters are Roley/Roland, Katherine “Kat” and Catriona “Cat”, and john who also has a secret name.