Research your genre. Read the most well-known books of the genre in which you want to write. Study the characters in those books and refrain from using too many of their characteristics.
Develop your characters. Base your characters on people you have met or know well. Make them personal and realistic. Give them flaws that make them more interesting and less similar to other characters.
Allow clichés in background characters. If you cannot avoid using a stereotypical character, then put him/her in the background. Making your minor characters slightly cliché can help you save space and words while writing, since the reader will immediately recognize the purpose that these characters serve and this will help you get your point across without spending too much time on secondary characters' development.
Give a cliché character a twist. Sometimes you have no other way to say something, but only through a stereotypical character. This is when you should try to give that character a bit of a twist. Give them a cliché physical appearance but make them act differently than what the reader would expect. Make them act in a stereotypical way, but look like no one else. Make them part-cliché, part-original and meet your reader halfway.
Recognize cliché examples to avoid. Some characters are widely known as clichés, making it easy for you to spot them and avoid them. Avoid the male or female character that was ugly in school but who has turned out to be the most beautiful as an adult. Avoid the evil other woman and the judgmental parents-in-law. Avoid the naive, good girl that turns bad and the man suffering from amnesia and cannot remember anything about his past.