Try to stay upright as well rather than bending over, it keeps your airways open. Also, I focus on markers 10-20 metres in fron to try and break up the tough hills.
If you lean - lean from the ankles so your body remains straight. Arm swing can also help as I found out this week. Swing your arms forward as though you were going to punch yourself under the chin (don't actually punch yourself tho).
Psychologically I find it helpful to aim for one lamp-post at a time.
conquer them! Treat every hill like a mini Everest. You have to be positive and aggressive, but don't push too hard if you want the rest of your run to be enjoyable