Tone up?

So I'm not over weight by no means, however I do want to tone up more. Found this great routine I follow. But I struggle with the eating part. The gods know I love to eat good home cooked meals! I need some help meal planning. I know if I start to really cut my quantity down and eat more (but smaller) meals a day I'll reach the results I want. I just can't seem to stick with "diet". I think meal planning will help. But I don't know where to start. Any advice or help is greatly appreciated!