Eat foods high in bioflavonoids, originally called Vitamin P. A bioflavonoids primary job is to protect the capillaries, keep them strong and to prevent bleeding. Lemons, green peppers, broccoli and rose hips are good sources of bioflavonoids.
Arnica cream or arnica gel is fantastic. We also use it for sore muscles and back pain.
Witch Hazel is great for bruises. Just keep a bottle in your fridge and put it on the bruise. It works best when you get it on the bruise as soon as it happens. But you still can use it if a bruise is not fresh. When you use the Witch Hazel it will take the colour out of the bruise or may not even bruise
Tea tree oil. When you get a bruise, rub some tea tree oil on it a couple of times a day. In two days the bruise will turn yellow and then two more days and it will be gone.
Apply an ice cube immediately to lesson swelling and discoloration from bruising.