Eat less, exercise more.

6' 4" (193.04cm), 180+ lbs (81.6466 Kg), 36 in (91.44cm) waist.
I've been 39 years of age for a while now. My waist expanded 3 years ago. Metabolism is slower. I eat less.

I am active in the summer and sedentary in the winter. I adjust my caloric intake accordingly.
12 Cokes a week, not 24. 24 beers a week, not ∞. 1 batch of cookies/ brownies every 2 weeks. Potato chips + dip ONLY after shoveling snow/ raking leaves. 1/3 pizza not 1/2. Captain's/King's Cut to Mate's/Queen's Cut Prime Rib..

You get the idea.

Best exercise is Push Away From The Table and Say "No Thank You",