I used to be a gym nerd too. My current approach: Screw common advice. Find what works for __you__. Take hints from algorithm design. Start small. Limit yourself to use variables you can influence, observe and measure. Come up with a system that embraces failure, try to make it anti-fragile. Experiment and enjoy the ride.

I'm personally quite chaotic and hate planning. Some weeks I hit the gym five days, some seven, some none. As such my training routine involves an auto regulating method which adjusts volume as needed. Periodisation (or lack thereof) is done with a simple recursive algorithm.

3/4 goes for nutrition as well. Screw counting macros, calories and weighing myself. If I like what I see on the mirror, great. If I feel that I'm getting flabby, I drop a PSMF day here and there until I look better.