Anticipate the changes in terrain and change your form and stride length accordingly. Now run several circuits of the hill using these images and see how your hill running improves. A quick ticket to oxygen debt. Hill races are rarely won by the person who is the fastest at the bottom . You must concentrate on relaxing and metering out your energy over the hill.
Many hills are steepest at the bottom and flatten out near the top.
A well run hill has you picking it up at the top and into the downhill transition. A short quick stride helps supply more fuel and oxygen than a long slow one uphill. This is the same reason that it is more efficient to use low gears and fast cadence when riding a bicycle uphill rather than high gears and a slow cadence. If you don't believe this , try running downhill with a pulse rate monitor and notice how much faster you can run at the same pulse rate than on the flat. Work on increasing stride length and using your armswing for balance.