A lot of good advice here. Samples:
"Show your passion for helping your customers solve problems - and talk to them like you talk to your friends. A real, enthusiastic, human voice is every small business's edge"
— Andy Wibbels, AndyWibbels.com
"Don’t start a company unless it’s an obsession and something you love."
— Mark Cuban, Blog Maverick
"When starting and growing your business, it's important to bootstrap with your own resources as much as possible."
— Mike Smith, Guerrilla Freelancing
"Become a cash flow king. Manage cash flow like there is no tomorrow. Know which vendors can wait and who needs to be paid right away. Always have some money on hand for emergencies and only borrow if you know when you can pay it back."
— Jared Reitzin, Mobile Marketing Watch
"Overconfidence is a killer. Question your business plan as much as you would question your nephew's business plan if he were to hit you up for a loan."
— Alex Tabarrok, Marginal Revolution
"Good word of mouth is the best marketing money can't buy."
— Muhammad Saleem, MuhammadSaleem.com
"An idea by itself is almost worthless. It's how you execute that matters. Focus on execution."
— Dane Carlson, Business Opportunities Weblog