The best way I have found to maintain a clean chain and drivetrain is fitting a removable Wipperman link to the chain . I find removing the chain is much more effective than cleaning it on the bike, and it also gives you better access to the rear derailleur, jockey wheels etc to clean and lube. The best degreaser I’ve found (aside from the very expensive Pedro’s stuff etc) is Citro Clean from Coles or Safeway; about $7 for a 700ml bottle.
Take off rear wheel and remove chain. Wipe down the chain with a rag (spray rag lightly with Citro Clean) to remove surface gunk and place in an old 1.25L soft drink bottle. Pour in degreaser (about + 100ml) and shake well . Remove chain (either cut bottle or use coathanger/old spoke to fish out) , rinse and wipe down and then inspect the links to make sure they’re all clean etc. If required, give the chain another quick spray of Citro Clean. Put b ack on the bike. Put rear wheel back on. It’s then best to allow the chain to dry for a bit, then lubricate each link while spinning crank by hand.
While the back wheel is off it is good to remove and clean the cassette if required. Babywipes do a really good job of this, or if really dirty a quick pre-spray with citro-clean helps.
Wipperman links are re-useable (ie you can demount and re-mount the chain as often as you like), whereas other similar products such as SRAM Powerlinks are single use (ie, once put on, you can’t take them off without breaking. The link comes in 2 parts. Take care to put them in a safe place when removing from chain as they can be easy to lose. It is a good policy to install a new Wipperman link each time you install a new chain as these will stretch similarly to a conventional link. Also note that they are directional, and the ‘arrow’ should be pointing up when the link is at the bottom of the chainline. Available in both Campy and Shimano 10s compatibility.
Slight warning , the citro clean can fade some paints such as the decals on Ksyrium SL wheels, so limit its use to the drivetrain.