Find 2 or 3 activities that you enjoy
Make sure you have easy access to participate in
those activities (ie, don't join a gym more than 10 miles from where you live or work)
Be honest as to whether or not you prefer exercising alone, with a partner, or with a group. A dedicated training partner, or training group (running, swimming, biking, hiking, weight-training, crossfit, etc), can increase your desire and dedication to your activity by up to 75%, if you are a "social person."
Make sure you have adjusted your dietary regiment. Quite simply, eating good food will give you more energy to be consistent in your physical activity.
MOST IMPORTANTLY: Determine YOUR primary POSITIVE reasons for becoming physically active. "I need to lose weight," "I don't look good naked," "I don't feel the way I used to."
Those are all NEGATIVE affirmations. Change them:
"I'm going to lose 12lbs in the next 3months," I'm going to look great in clothes and Out of Clothes for my beach trip next year," "I'm going to work towards feeling how I felt 5/10/15yrs ago."
People often underestimate how dependent your mental health and attitude will affect your results for physical fitness.
Hope this helps you.