Ken is right, I've read Minn's article and it's good. To give a quick answer to the question, though, you need:
1- The smoke pump
2-battery to drive the pump, charge jack and switch
3-muffler set up for smoke oil delivery
4-smoke fluid tank
5-plumbing from tank to pump to muffler.
6-room in the plane to stuff it all.

The pump controller plugs into a spare channel on the Rx, and you can activate it by a Tx switch.
Gas engines work best, then 4-stroke glow, then 2-stroke glow, but they can all be made to work.

Beyond that, read MinnFlyer's article.