My rules: Lube every 300 miles, clean and lube every 600. This may vary depending on riding conditions. I'll hit it more often if I've ridden in the rain, or traveled down dusty roads.
There are gadgets out there for cleaning and lubing, such as the Grunge Brush and Z-Oiler, respectively (check out www.compacc.com
to see these). I have heard people speak highly about both of these.
The most often recommended do-it-yourself method entails cleaning the chain with a rag soaked with kerosene. With the rear tire up, on a stand, hold the rag around the chain with your left hand and spin the tire backwards with your right hand. Done this way at respectable intervals, there is usually never a need for brushing. If there happens to be some stubborn crud, a toothbrush will work well. Just rinse it off really well before using it on your teeth again. The chain will clean up easier if it is warm, so do this right after riding. Don't ever try this method of cleaning with the bike running and in gear; there's a few people around who can no longer count to ten because of the outcome.
For lubing, take your pick. There are specialty chain lubes and waxes galore. Some people prefer lube, some wax. Buy one of each and make up your own mind. Or, follow the Honda manual and use gear oil (just use the soaked rag method to apply it to the chain - you don't want any lube getting on the rear tire).
You'll hear a lot of people telling you to never use WD40 on an o-ring chain because they claim that WD40 will seep past the o-rings and dissolve the packed grease. Probably not bad advice given all the options.