I'm very happy to report that once you've scrubbed the heck out of your cast iron skillet, seasoning is pretty much a breeze. I didn't know this, of course, until a kind commenter left directions on "Seasoning Your Cast Iron Pan" on the above-mentioned post. Thank you!
Re-seasoning your skillet after a thorough cleaning is absolutely critical. The "seasoning" is the coating, or layer that makes the skillet non-stick. The cast iron skillet is essentially useless when it's not properly seasoned. Luckily, you don't need any fancy equipment or cleaners. All you need is your skillet, an oven, and some oil or grease.
Now, there's a lot of debate about what kind of oil to use. And people seem pretty stuck on their choices. From what I gathered, the most traditional folks use bacon fat or lard. I didn't have any of this stuff on hand, though. Other people use canola oil or vegetable oil and there is debate within these, too. One site I read said never use vegetable oil, but there are plenty of people, including the author in the tutorial above who claim to use it with no trouble. Because I cook most often with coconut oil, I opted for that and hoped for the best.