You will slip up and have bad days/weeks/etc. Just acknowledge that you messed up, try to learn from it so it doesn't happen again, and start fresh RIGHT THEN. Guilt, regret, and self-hatred do not help. Love yourself enough to move forward and focus on the now.
Too busy to cook a real meal but want to get your veggies in? Take your meal-in-a-box (let's say it's a box of tuna helper) and add a bag of frozen veggies to it, making it more nutritious (and it feels like you can eat more).
If you're like me, exercising without a point is boring. Set goals like setting a personal record for your 5k, holding your yoga pose for longer than you've ever before, or increasing your weights every 3 weeks. Better yet? Sign up for a race or competition for extra motivation!