Cool it down
Ice packs or cold compresses during the first twenty-four hours, particularly when used promptly after being injured, could help minimize bleeding and swelling. Raw steaks that have traditionally been put on black eyes were done so because the meat is cold, not because it has any special healing properties. Ice wrapped in a washcloth or a baggie of frozen veggies are more suitable steak substitutes.
Avoid a swelled head
Keep your head elevated (sleep with a few extra pillows, for example) to help limit swelling and pooling. Over-the-counter pain relievers, such as acetaminophen, can also help relieve discomfort. Avoid aspirin since it decreases the blood's ability to clot.
Apply moist heat
On the second day following the injury, applying warm washcloths or compresses can help increase circulation to the injured tissue. This aids in the re-absorption of any leftover blood that has collected at the injury site, promoting healing.
I cut and paste this from a web page because it was quicker than typing - but it is all stuff I have found to be true.
If you are feeling at all nauseous or your vision is blurred you may be concussed and should take it very easy (and drink plenty of water) until you are sure you are not.