Much of the info below wouldn't be new territory for you, but I hope it helps. The points I wanted to emphasize: measure, prevent plateaus, and that less is more.
Losing weight and putting on muscle should come easy initially, since you've had a break for a while.
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Most importantly, 'measure':
- Keep note of your 8-rep max. Make sure you're not pushing yourself too far. Most folks feel embarrassed to add on the tiny 1.5-2 pound weights to what they're currently lifting. But thats thats the sort of increment you should be looking at -- 1.5-2 pounds every other week. This can't go on infinitely.
- Vitals: blood pressure, creatinine levels, pulse rate, pulse deceleration time. If you're doing it right, you should see improvements on some of these. Most folks choose to ignore deceleration time.
- Muscle repair time. How long they stay sore. Things that've reduced repair-time for me: glutamine, multi-vitamins, fish-oil, upping the protein intake (fish etc.).
- Optimize the diet --> repair time --> strength-gains relationship. There certainly is a level of protein intake (differs per person) that'll result in maximized gains & lesser repair time.
- Quality of sleep. Note down how rested you felt when you woke up. Tune your diet/vitamin intake for better sleep & more vivid dreams even.
- Food intake. The exact items you've consumed, vitamins involved, calories (tagged by fat, carb, protein).
- Productivity, through measurable values: pomodoro's, lines of code, emails replied to, calls made, blog posts written etc.
- Energy levels during the day. Times you felt sleepy, irritated, low-on-resolve etc.
- Body function: pains felt, skin irritations, bowel-movements, urination-frequency.
- And obviously, you'd be tracking body weight constantly (preferably on a daily basis). Personally, I wasn't too bothered about tracking inches on my biceps and such.
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While it might seem mundane to track all of that stuff, you'll have a ton of fun coming up with interesting conclusions from the data. If you stick with it for at least 8 weeks -- measuring, analyzing, implementing, improving -- you'd have turned yourself 80% better.
Also,
- For a diet, I'd suggest Tim Ferris's 'slow carb' variant of the low-carb diets that are all over the place. It works quite well. Cheat-days are mandatory.
- My workout consists mostly of compound lifts (squats, bench etc.). I'd set aside a couple of days each week for cardio -- lasting about 25-30mins. Resistance training about 3-4 times a week, and keep switching workouts (you'll find a plethora of interesting ones at the bodybuilding forums) every month or so, to prevent plateauing.