Every couple hundred miles, I take off the rear wheel, and spray the cassette liberally with straight Simple Green, and let it sit while I do the chain. I have a gizmo that clamps on the right rear dropout so the chain can run without having a wheel in place, and I then spray down the chain, the rear derailleur, the front derailleur, and the chainrings with Simple Green. I use a fingernail brush on the chainrings, and a toothbrush on the rear derailleur jockey wheels, and then run the chain between the fingernail brush and the toothbrush. Then I rinse it all off with lots of water from a hose - a gentle spray, not a jet. Then I use the fingernail brush on the cassette, and hose it off.

At the same time, I clean the front and rear brakes, also with Simple Green, and the doohickey where the cables run under the bottom bracket, and wash the whole bike, including using a brush to scrub the brake tracks on front and rear rims.

Once it's all dry, I use Finish Line to oil the brake and derailleur pivots, the doohickey, and the chain. Once it's had time to penetrate, I run the chain through clean paper towels to remove the excess, and check the shifting, front and back all the way up and down the range, and adjust cable tension if necessary.

Every so often, I check the chain wear with a Park chain checker - a cheap little piece of metal that can save you lots of money on cassettes! At 900 miles I'd be surprised if you've worn your chain much, but then again you say you haven't cleaned it yet and ride in dust, which when mixed with chain lube is an EXCELLENT abrasive!