Um, you don't throw your food, you throw the line. Tie a rock to 40-50 ft of strong, smooth cord (or attach the cord to a small stuff sack and put (a) rock(s) in the sack). Attach the other end to the food bag (a large nylon bag will work fine, I use a silnyl stuff sack of appropriate size). Throw the rock over a stout tree limb about 12' or so off the ground or over the bear pole line. Pull your food up, tie off the line somewhere convenient (or do a search for the PCT bear bag method and use that).

If you can find a good tree and limb (or have bear poles), it's pretty simple.

Other sources of info that might be more clear:

Click "Search" here, set "Keyword search terms" to "bear bagging," set "Date range" to "Newer than 1 year," and get a list.

http://www.backpackinglight.com/cgi-bin/backpackinglight/bear_bag_hanging_technique.html

http://pweb.jps.net/~heber/bearbag/bearbag.htm

http://www.princeton.edu/~oa/training/bearbag.shtml