If you have enough wind, you can drop both the main and jib, and the wind on the hull will provide enough drive to push the boat downwind into a slip. It doesn't require a lot of wind - just enough to push the boat fast enough so that she has steerageway.
If the wind is light, and you need some sail to help you move the boat, I would recommend that you use the mainsail, rather than the jib. The reason is that sailboats don't have brakes, so you have to keep your speed under control as you enter a slip. If your jib is hanked-on, then you can't furl the jib to control your speed. If the wind gusts when you are close to the slip, the jib will fill and accelerate the boat too fast, and something bad is almost sure to happen. I prefer to use the mainsail when docking downwind under sail, because I can ease the main halliard, allowing all but the top part of the sail to fall to the deck. Only a small part of the mainsail will still be raised a few feet above the boom, and that will be enough to move the boat into the slip. If a gust of wind comes along, that small bit of mainsail probably won't accelerate the boat enough to present a problem, but, if it does, then I can just let the halliard go and let the rest of the mainsail fall to the deck.
If the jib is on a furler, then you can furl the jib enough to limit the boat's speed as it approaches the slip.