Getting your bike chain sparkly clean (solvents / degreaser etc.)
First, you'll need a solvent. I use a biodegradable and water-soluble cleaner. Oomph (purchased from Bunnings) does the trick nicely, though there are plenty of others. You can get it from a cycling shop, but you'll pay much more for the same thing! No need for those nasty petroleum-based cleaners, which are hard to hose off and nasty for the environment.
This is available from Bunnings - cheap and highly effective.
Next, you'll need a chain cleaner. You could decant the degreaser into a spray bottle and go over the entire chain with a toothbrush, but this is laborious and messy. A chain cleaner contains the mess and does a quicker and more thorough job. I've used several over the years, but have never looked back since buying the Park Tools model; it contains a sponge to trap excess solvent, and a small magnet to collect metallic particles.
The Park Tools chain cleaner is very well built. Mine is about 4 years and still going strong.
Pour solvent into the cleaner, and clean the chain by turning the cranks backwards for at least 20-30 revolutions. For a complete clean, pour some solvent into a spray bottle and carefully spray solvent onto the chainrings (inside and out), avoiding the bottom bracket area. Use an old toothbrush to scrub off accumulated grit and dried lube. Hose down the chain by turning the cranks backwards, avoiding spraying the bottom bracket area. Using the fine 'mist' setting on your garden hose trigger (definitely worth getting one with variable settings from the hardware store), lightly spray the cassette to wash off any solvent and loose grit (the aim is not to do a thorough cassette clean here, that's a separate job, just to get rid of the excess solvent).
Spin the cranks backwards rapidly several times to remove excess water - dropping the bike gently also helps shakes off excess water. Run the chain backwards through a clean dry cloth until fairly dry, then allow to dry completely (several hours usually) before applying a fresh coating of lube. Let the applied lube dry for several hours, or overnight (if you don't do this you'll get wet lube flicking all over the place, kind of undermining your hard work).
I highly recommend ProGold ProLink lube for road applications - see my earlier blog entry.