learn the rule
compliment / complement
compliment is a noun (a polite expression of praise) or a verb (to give such praise).
- That's a lovely compliment.
- She complimented me on my potato salad.
complement is a noun (something that completes or goes well with another) or a verb (to make complete or enhance).
- The wine was a perfect complement to the meal.
- Your sock complements your outfit.
- The team has a full complement of staff.
The two are often confused because they sound identical and look almost the same. They mean entirely different things.
Remember by the vowel. Compliment has an i, as in nice (which is what you're being). Complement has an e, as in enhance or complete.
I'd compliment you on your spelling, but you wouldn't complement the rest. You'd still look stupid. And ugly.