exercise help for the completetly sedentary

Lots of different ways to get in shape, but one popular way that works is to do full-body strength training every 2-3 days, and cardio on your non-strength days, with 1 rest day per week.

For strength, start with a bodyweight-based program, like Nerd Fitness (google it).
For your first workout, only do half the goal number of repetitions, so you can move the next day.

For cardio, pick any activity you enjoy that gets your heart rate up - jump rope, dancing, DVDs, sports, cycling, running, swimming, etc. Start with only 3-5 minutes your first day, and add 2-3 minutes each workout, until you're up to about 30-60 minutes per day, depending on your goals. If you choose to run, look into the C25K program.

If you have any medical issues, get clearance to exercise from your doctor.

If you encounter any unusual pains along the way, don't work through them!

Post progress reports!

Jog the dog. Then come home and do some push ups, pull ups, sit ups, squats, dips, etc... Every day that you exercise, do a little bit more than you did the last time. This could be a little further dog walk, 1 more push up, a more intense dog walk (up hills, faster tempo, etc...) Just keep building and building.

check out the Couch to 5K ap. its awesome.

I was inspired by the book Eat, Move, Sleep to start making a lot of small changes. An example is parking further out from the doors of work, stores, the library, etc. At work I would typically walk about 60 steps to the front doors. Now, I park further out and walk twice that. That doesn't seem like much at first glance, but at 5 days a week at a minimum that is an extra 600 steps per week and if I go out to my car for lunch it could be as much as 1,200 steps per week. Most walking sites will estimate a mile to be between 2,000 and 2,500 steps. Just doubling my distance at the minimum at work (not including all the stores, library, etc.) I could add a mile every month or 12 miles a year of walking.

Another example is that I have taken up using a slow cooker. I don't like salad (although I do now with Wendy's Pomegranate Vinaigrette salad dressing!) and I can't stand cold vegetables, but with a slow cooker I can take any meat on my grocery budget and make it tender with delicious vegetables and a little broth. I can then reheat on the stove or the microwave or even put it in a thermos and take it with me with a bowl and fork/spoon. Less temptation to eat out.

One more example of getting better sleep is to make sure I turn the lights out and take the temperature down a little. Sleep under blankets. I don't like the cold, but I notice I definitely sleep better when it's a little cooler and I am in complete dark. I do listen to some light meditative types of music, but often I find I miss just drifting off in the dark silence as well after too many nights with music. If you have a smart phone try one of the many radio apps out there as most of them have sleep timers on them to turn them off after you fall asleep. I also try not to sleep in on weekends anymore. It is common advice to get up around the same time on weekends as you do on weekdays within reason (I'm simply not getting up at 5:30 AM on weekends!), yet I never took it. Now I am trying to keep to that and I do find it to be true, my sleep overall has improved by going to bed at a decent hour on weekend nights and getting up fairly early on weekend mornings.

You said you don't have the money for a gym membership. Understandable, so I won't go into fitness devices like the Fitbit or Jawbone, but even a simple $20 pedometer can be helpful. It is encouraging when you can see yourself making progress by walking more steps per week. You could also check out some walking clubs or groups Online and get out on the weekend or whenever you have the time. The socialization will help keep you happier and also give you something to look and work toward, all while getting healthier.

Best of luck!

Walk the dog longer. My dog is my walking buddy. When it's nice out, we'll walk up to 6.5 miles. We also do run intervals together.