When building a character, it’s helpful to base her or him on someone you know. After all, you want your book characters to be realistic. How better to accomplish this than constructing them from real people?
Select a person to observe for a few weeks. Follow your subject’s daily routine, carefully watching actions and reactions to each small setback and triumph. Take notes, or perhaps video, to help you remember.
Consider using your subject’s real name. S/he will be flattered to discover their life has been captured for posterity in your words.
When you get to the villain, think of those who have wronged you. The ex-husband who was still married to his second(!) wife, the evil co-worker who calls your boss’s attention to your every error, the neighbor whose dog nearly attacked you as you got out of your car in your driveway. The possibilities are endless.
Feel free to exaggerate their vileness. Or should that be villainy? Either works for me.
For your hero, you might prefer to dream a little.
Gerard Butler in a kilt.
Richard Armitage in a cravat.
Tom Hardy in anything. Or nothing.
Look around. Characters are everywhere!
Seriously? Character building
How to Write Lovable Heroes — “The Creative Penn”
TSTL (Too Stupid To Live) heroines explained — Anne Marble