This is a 12 week training programme to prepare runners who are fairly new to running to run their first half marathon. If you have never run before, I suggest starting with the Beginner 5km programme followed by the beginner 10km programme before starting your half marathon plan. Before embarking on the programme you should be currently able to run at least 8km comfortably and should be healthy and injury free. You will need to be able to do 3-4 workouts per week.
Run at a comfortable pace. This is only the start of the programme and you don't want to kill yourself on the first day! Your pace should be easy enough that you are able to talk and you should feel you could carry on at the end if you had to.
LSD runs are all about time on your feet and not pace. If you need to walk then you may, but make sure it is a brisk walk and try to limit your walk to minute. In the beginning you might want to try a run/walk strategy of run 9 minutes, walk 1 minute.
Also keep the pace at an effort where you can still talk and resist the urge to push hard, even if feeling good.
Start out easy and build up the pace to a bit faster than your "Light run" pace - just where talking starts getting a little tough. watch for running too hard, you should be "pleasantly tired" at the end of the run and not "dead".
Even if you are feeling good, resist the temptation to turn the run into a race, stay controlled, otherwise you are inviting overtraining and injury.