Use a colon (:) to signal that is list will follow. Just be sure that you write a complete thought before the colon.
I bought three things at the store: milk, bread, and peanut butter.
Notice that the words before the colon make a complete thought: I bought three things at the store.
Here are more examples of the correct way to use a colon with a list.
My brother eats three things: hot dogs, chips, and ice cream.
We have four good stores near us: Walmart, Target, CVS and Dollar Tree.
Janet excels at three sports: track, basketball, and volleyball.
Look at this wrong sentence. My three best friends are: Mary, Sue, and Josie.
My three best friends are is not a complete thought. Therefore, we cannot use a colon in this sentence.
Use a colon at the start of a list if the words in front of the list make a complete thought.
It’s your turn. Look at this sentence. Does it need a colon? Mom planted three things in her garden squash, beans, and tomatoes. Did you find a place where the colon should go? Good for you!