IME, one of the "tricks" is to set your goals so low that you cannot possibly fail.
E.g., if you're still building the habit, 5 minutes of walking or 1 pushup is a win. You can do more if you want to, but doing anything is better than doing nothing. Don't celebrate it with a candy bar, but do celebrate it....even if it's just smiling at yourself or sitting there and feeling your own success for a moment.
After you've actually built that habit, when it's easier to do something than nothing, then you can work on scaling up. If you're already past that step, awesome.
I'm also gonna say to be careful with FDA guidelines for diet. Do your own research, and I am neither a Doctor nor a nutritionist...but I can read studies as well as anybody. Their recommendations are based on lobbying, not science. My life got better when I decided to do almost the exact opposite of what the FDA recommended at the time. YMMV. I think Mediterranean is a decent option, with some caveats.