This is from my own experience...
1) start off slow and with a small distance. Mix up walking with jogging. Eventually increase jogging and reduce walking. When you are comfortable, increase your distance. You will find your sweet spot for speed and distance.
2) find a good route that doesn't have too many inclines. Avoid areas that may make you anxious (I avoid residential). Being relaxed is key!
3) never start off too fast if you plan to do your usual distance, you'll suffer towards the end.
4) track your jogs with an app like run keeper. This will record distance, time, average speed etc.
5) I find that listening to fun/upbeat music helps me push on to further distances. I can do 7 miles without too much trouble now.
6) go when it is cool, because you will warm up a lot when you jog.
hope that helps