Take your head of cauliflower and with a paring knife cut away any brown spots. Remove the green leafs from the head of cauliflower. Cut the head of cauliflower into florets, removing and discarding the core. Wash the floret well and let them drain until completely dry. You can also pat dry with paper towels. You don't want them wet at all.
Add the florets to your food processor, I do half of the head at a time. Working in batches is the way to go. Pulse a handful times of times or process quickly just until it is chopped and has a rice-like texture. Don't go too far or it will be mush. Alternatively you can use a hand grater but it takes a TON of time and it's a hell of a workout.
Heat a small amount of olive oil or coconut oil (just a couple of teaspoons) in a skillet or frying pan over medium-high heat and add the cauliflower rice. Stir it around and allow it to cook for 5-8 minutes. Just until it is tender and barely starting to brown. Season with salt and pepper, to taste or any another complimentary herbs or spices to the dish you are serving it with, that you'd like. Serve and enjoy.