Goals are easier when you make commitments.
I hate being part of a fad, but a buddy wanted to get into better shape. Asked me to commit to a Tough Mudder with him. So I figured it would get me into better shape too so why not. You have to set small goals. I started with 4-5 days a week, walking a mile, running a mile,.walking another for a month. Then walk 1, run 2, walk 1 for another month. We ran a 5k fundraiser. Then another. Before the mudder I got up to running 2-4 miles a day for the last month. I threw in lots of push-ups and pull-ups throughout. In the end, I wasn't in great shape, but a lot better than I had been. Harder and harder to keep it up. But its easy enough to find friends and family, even coworkers doing some fundraiser 5k every other weekend. Just ran one today, 50+ people in our group for a PH fundraiser. I sucked, but knowing it was coming, I got out and ran a few time over the last couple of weeks even though I was nursing a sinus infection.
Other simple stuff: commit to doing some physical activity two days a week with your kids or friends. Biking, jogging, hiking, walking the dog or all of the above. I have different groups of friends I do different activities with. Get a fitbit or any other step counter. Give yourself a reason to do a little more all the time. Park farther out in the lot at work. I work an office job, I started using the farthest bathroom. I'm in my thirties, but a guy I work with is nearly 60. He had open heart surgery a year ago and has been walking the halls or the lot at work 2x a day, now I walk with him. I fill my water bottle only half way so I have to get up twice as often. Sounds silly, but when you start counting every step, you make every step count.
What works for one may not work for the next. Find what you can work for and what works for you. Get out there!