The first few steps.

I believe the first step to any kind of workout is to talk with your doctor.
After this talk the workout is all about you; you are the only one that can make a difference to the way you want to look. Nobody can do this for you.

You can join a gym, but by joining a gym, you have to go, make a commitment and stick with it. Most gym's will offer free sessions with an instructor, ask to make sure the instructors are qualified.
In choosing a gym, think about the area, if you have to drive too far you may not want to go; if you should drive past on the way from work, you could take the time and work out.