Time based walks are fun and easy. Start off with a manageable amount (20 to 30 minutes) and just go at a comfortable pace. Gradually increase your time. Over time you will burn more calories with regular walks than a single marathon session. Ideally, walking 40-45 minutes per session a day is the minimum you want to do in order to get your heart working.
If you have a smart phone, there are some great apps that you can install which will track your steps. One such app is Accupedo. It will sync with other useful apps like MyFitnessPal.