Well, the best way to get a good number of off flavors into your beer is to use the Siebel sensory evaluation kit. The upside of this is that you will get a good dose of each of these flavors and you can clearly identify them in the samples. The kit is also good for something like a dozen people.
The big issue with this is that the kit is 180 dollars. Luckily, I've been through it 3 times and it helps more every time.
Since that is prohibitive, you can start with easy to achieve off flavors like skunk. All it takes is a few minutes in the sun for that one!
I'm taking the BJCP test on the 10th. Hope I pass!