To avoid pain run less distance at a slower pace. People generally build up way too fast. I had plenty of problems in my late 40's when I tried to run and went at it like when I was a kid. But when I slowed down and built distance up very slowly I had no problems. Now I run marathons and have averaged about 45 miles/week for 2014.
Regarding form, I would say it's not something you need to focus on. Do try to run as straight up as you can, like you're a marionette suspended from strings with your legs moving beneath you (probably same thing said another way as "pretend you're running on thin ice"). But other than that your body will mostly sort form issues out unconsciously as you very slowly ramp up running mileage.
Regarding form, I would say it's not something you need to focus on. Do try to run as straight up as you can, like you're a marionette suspended from strings with your legs moving beneath you (probably same thing said another way as "pretend you're running on thin ice"). But other than that your body will mostly sort form issues out unconsciously as you very slowly ramp up running mileage.