@Shalok Holmes,
Are you looking for something campy or cliché? If so, then consider how witches are normally portrayed in fiction. It's a trope, actually.
Also consider if you want this to be an ugly duckling to swan type of character or someone who's just ugly and rotten to the core. A beautiful person on the outside who is awful on the inside can be a very powerful character (I am assuming you're looking to write this...?).
Also, try not to lean on stereotypical easy uglification of, well, anyone. That means avoiding associating ugliness or creepiness with:
- A darker skin color
- Aging
- Obesity
- Female baldness
- Disability