Here are some steps to get you started for the next six months. This is what has worked for me.
Step 1 - Set a "Why?" for why you want to get into shape.What do you want to be able to do when you reach your fitness goals? That will be different for everyone. For me, it was a combo of hiking, playing with kids, getting a lower rate for health & life insurance, get sick less often, and be able to tie my shoes without grunting.
Step 2 - Set goals and milestones on what that would look like going out for five years.Some five year goals were like hike 60 miles over 3-4 days, hike the Appalachian Trail, run Beach to Bay is in there somewhere. From about 2 years out I had my ideal weight, size, and some other measures of fitness for me such as being able to do 10 pull ups (5-year plan, but about to move to a 2nd year milestone) and have 6-pack abs. Then, I really broke down the one year milestones. See some of my goals here.
Step 3 - Get started.You have to create a new set of habits to break or replace your old habits. Those habits have been formed over a lifetime of gradual changes, so you have to replace them with gradual changes in the opposite direction.
Weeks 1 & 2(1) Replace soda with water. Need caffeine, 1 cup of coffee with cream & sugar per day in the morning. Ideal water intake should be 1/2 of your body weight in ounces. You'll pee a lot, but you'll flush your system and stay hydrated which is needed for your joints and muscles. I just learned of a smartphone app called Water Your Body on my Android phone (iTunes link) and it reminds me to drink a glass of water every hour between 8 a.m. and 10 p.m. I had to make some adjustments to the settings to make sure that it was an 8 ounce cup I was expected to drink.
(2) Track your calories on MyFitnessPal (myfitnesspal.com). I didn't make any changes at first. the point for two weeks is to just get into the habit of tracking your calories. So, what if you go over those calories every day during the two weeks. The point is to get into the habit of tracking your food and seeing what you really eat every day.
(3) Exercise 5-6 days a week for 7 minutes with calisthenics every morning. I used another app called VirtuaGym on my Android, and for the first two weeks did the 7-minute home workout (no equipment). The hardest part was actually doing the workout in front of my family. Once I got past that, I was golden and this has now become my routine, exercise in front of family. This workout is not intense at all, that's not the point. The point is to get into the routine of working out, and gradually work your body back into a fitness regimen. Too much too soon will burn you out, and you'll quit, most people do.
From Week 3 to my First Plateau (Six Months):1. Keep drinking that water, and don't give in to soda. (I have had less than 2 liters of soda since January, and lost track of the water.)
2. After tracking your food for the first two weeks on MyFitnessPal, I started to make adjustments to the serving sizes, and gradually started to incorporate veggies because I needed to feel full and realized my favorite foods were killing me. I still eat my favorites, just less of it at one time. I had a piece of cake at work this last week, and my coworkers were freaking out thinking that I caved. They were shocked when I replied, "Who said I couldn't eat cake? Everything I've eaten is what I wanted to eat, with healthier choices in that." Felt good to say it, but it took me a few months to get there.
3. My workouts have gradually increased in intensity, but I've mostly stuck with 20-30 minutes a day, five days a week, using VirtuaGym home workouts. I walk when I can, stand at work in the office (I have a science lab style desk for some reason), I also practiced with Jacob's baseball team. That burned a lot of calories. It was mostly cardio-style calisthenics from VirtuaGym, so now I'm now looking at some strength building exercises to get more toned muscle to burn this fat because of the plateau I have reached.
Hope that helps.