Low Hot Water Pressure; Cold Water Fine

['Hamas' Jenkins]

A few days ago it felt like someone turned our water off mid shower. Now, given that I try to make a habit of paying bills, I knew that it couldn't be due to delinquency. Oddly, the cold water isn't affected at all, but the hot water runs at about half of its old pressure Upon further Googling, it seems that when such issues arise it is often due to a blockage in the hot water heater, often due to sediment.

The question is "What do I do about it?"

My knowledge of plumbing is low, although I can at least fix a running toilet.

I've read that draining the water heater is recommended, but the success rate seems fairly low. One guy recommended putting a dime over the only running spout to create back pressure to blow out the sediment. I'd rather not turn a shower head into a mortar shell, so I'm laying myself prostrate in front of your collective home repair acumen.

Call a plumber is my first thought, but other cheaper and quicker potential fixes that don't damage the integrity of the tank or pipes would be greatly appreciated.