Tip #1 - Pay attention to details. I just spent two weeks distributing my email address without the "_" because I forgot it had one. Don't forget the details!
Tip #2 - Read. Not just marketing stuff, read things for fun, too. It'll improve your mental abilities, and therefore your marketing - and income.
Tip #3 - Work for something other than money. I don't mean barter, I mean work towards what money can BUY you - not the money itself.
Tip #4 - Never count someone out as a JV partner. Find a great product on Clickbank that you're interested in? If it relates at all to anything you're currently promoting, send them a message. You never know.
Tip #5 - Set yourself apart. Be different. Be yourself. Don't be "professional" the way some people see it... Don't refer to yourself as "we" if you're a "you". People relate better to those who are just like themselves.
Tip #6 - Don't neglect your warrior friends. Some of my most lucrative business deals have been built through this forum, and some of my best online friends have been made here. Don't take it for granted.
Tip #7 - Monkey see, monkey sell. Act as your customers do, and you'll understand them better. Which means you can sell to them better.
Tip #8 - Outsource what you don't know. I don't just say that because I'm a copywriter, I say it because it's more profitable that way. I outsource all of my graphic creation, because to be blunt, I suck at it. It would take me longer (and cost me more) to learn "not to suck" than it would to pay someone who already knows how to do it well.
Tip #9 - Underpromise & overdeliver. One of the core principles of sales. Promise enough to get the customer - deliver enough to keep them for life.
Tip #10 - Be honest, be yourself, know your strengths & weaknesses, and have fun. With just those four things, you can make a living online. I promise.
Hope those are informative... I'll post some more secretive stuff later on.