Place your workout bag in the front seat of the car so you are reminded to exercise at the gym on your way home from work. Consider recruiting an exercise buddy - a spouse, family member or friend. Keep it simple and convenient. For example, I walk with a work colleague about three times each week during lunch. We e-mail each other every morning to set a time, then remain flexible if the other is not able to walk.
Convenience can be the key to maintaining a regular exercise program.
Consider buying home exercise equipment or exercise videos. Consumer Reports Online has excellent reviews of current equipment. Small group training is a trend that is catching on fast in the fitness world. Or, if money is no object, hire a personal trainer to get you started.