Running is the most popular exercise method. If you're thinking about running but not sure how to start then I think I have some suggestion for you.!
Last two years, I was like general office people, I can't even continuously run for more than 800m(half a mile). Now, I've been to 2 full marathon (42.195 km ) which took me around 5 hours of continuous running, non stop.
To start running, I suggest you to set a goal first, it doesn't have to be a big and hard goal.
Start with setting the goal in mind "Okay, I want to run 50 minutes continuously, non-stop", but that's the goal, it doesn't mean you have to be able to do it right now or very soon.
Then after setting goals, in a week, find at least 3 days for running, the rest is rest day. Resting is important too, it's not good to run everyday. Your muscle need a rest and recovery.
In the running day, follow this training schedule, http://www.superskinnyme.com/beginner_running_program.html.
Now, if you're also running for losing weight, then calories play very important roles.
Not only running is enough, but you also have to control your food consumption. Suppose daily requirement(varies depends on each person) is 2000 Cal, it's important that you consume less than 2000 Cal, to lose weight.
If you have burn 300 Cal from running then you can consume no more than 2300 Cal.
Don't base your calories intake amount on your exercise, don't think like this "I've burn 300 Cal, so I shouldn't consume more than 300 Cal this meal" No!, This will make yourself starving. Focus on trying to be below daily requirement+exercise. If you need application to track your calories, I would suggest 'MyFitnessPal', it's totally free.
Rather than calories control, it's important to consider the nutrition facts as well. Try to avoid and limited food with high fat, that's not good for your body.
Running will totally change your life, I promise. Once you're into it :)
For me personally, I use 'Negative Split' technique in my running session. Negative split means you run fasters as you run further. So the further kilometer will be faster that the first few kilometer.
Health is the most important thing in this world, love come seconds, and money come third :)
Don't stop taking care of yourself. Thank you for reading.
I'm still newbie, if there anything I could improve my article, leave me comments. :D