Don't eat anything you like or want. HAH!
Seriously, basically it means to eat to fuel your body. Lean protein, veggies & fruits, whole grains & legumes. Pretty much what we all know by now...keep down the fat, caffiene, aspertame (yuck!), sodas, white flour, sugar, etc.
I think the main difference between so-called "dieting" & eating clean is, as I mentioned, you are eating to fuel your body for your daily life & all those workouts! It helps me to eat small mini-meals every 3 hours or so, when I can. I always include a small amt. of lean protein & a veggie or fruit, usually a grain. Other people do better on a more traditional schedule, but the basics "remains the same".
Just don't forget the importance of eating ENOUGH food & not skipping meals, esp. in the morning. Took me years to learn that, even though I knew better all along. A couple of years back my weight loss hit a plateau. In desperation, I starting eating breakfast, & 2 weeks later had lost 5 lbs.
Anyway, just my 2 cents. Other people here can give you a better synopsis as they are truly educated!
Take care & let us know how it's going. We're all in the same boat.
Ruth