Use a sharp kitchen knife to gently remove the tough outer leaves from around the head of the cauliflower. 

Wash the entire cauliflower under warm water and dry it with a clean kitchen towel. 

Remove the stem of the cauliflower with the knife and stand it straight up on a cutting board. 

Use a small pairing knife to remove any dark/brown spots. 

Cut the cauliflower in half through the center and cut each half into quarters. Remove the stem centers, then break up each quarter into florets with your hands or knife. 

Place the florets in an airtight container or zip bag and refrigerate for up to a week.