How would sortition work to choose legislative representatives?

"The Common Lot: Next Step for Democracy" advocates that sortition (random selection) be used to select among qualified citizens who are willing to serve in the legislature.

In order to be entered into the pool for random selection a citizen would be required to do two things.
First: register (just as one registers now to vote). Placing oneself in the lottery pool should be voluntary.
Second: pass a civics test in order to demonstrate basic understanding of the legislative process. This test should be no more difficult than the one required to obtain a driver's license in the U.S.
Accomplishing those two requirements, the citizen's name would be placed in the pool for random selection to serve in the legislature.