Not much you can do. The underlying cause is generally regarded to be from microscopic muscle tears, which are the result of unaccustomed exercise. Really, the only cure for that is time and your bodies natural healing process.

You can speed that up a bit by making sure your diet includes all the things necessary for rapid recovery, such as a full load of vitamins, proteins, and amino acids.
Increased blood flow to the area will also help speed healing, so gentle massage and heat will help.

Not much you can do to alleviate the actual pain without resorting to pills though. In the future you can limit soreness by properly warming up and stretching before serious exertion.