Beginning photographers think about cameras. Intermediate photographers think about composition. Advanced photographers think about light.
Just keep shooting. You're not getting any better thinking about doing it. GO DO IT.
As for business advice: Give a 2% discount for payment within 10 days. No accounts payable department will be able to resist it. And charge for waiting -- if you are scheduled to do something and then the client isn't ready, charge a partial fee for waiting, like a taxicab.
Don't work for free. If you don't value your work, why should anyone else?
Put agreements in writing. Use email whenever possible to conduct business because you have a timestamped verifiable record of communication.
Learn what you don't want to learn about photography and the rest will come naturally!
Guarantee your money.
Don't spend what you don't have.
Buy a sturdy tripod.
To keep the passion alive.
Best advice ever was a pro-photographer telling me that his best time was at school. That saved me from running my business.
Shoot what matters to you. Don't get caught up in the "rules".
If you are not slightly embarrassed about what you charge, then it isn't enough.
For business, photography, and life, and no pun intended - focus, focus, focus.
Enjoy your hobbies.
Quit and become a doctor.
If you're not meeting the bottom line, stop wasting your time.
If you are good at what you do... don't do it for free.
The quickest way to make money from photography...is to sell your camera (through KEH, of course).
My favorite wedding photography advice I received- When it is time to have the bride throw the bouquet, ask her to start with a fake throw, then a real throw. You get a great shot of her throwing but don't miss the catch.
Underexpose Kodachrome by 1/3 stop.
Compose and make sure the lighting settings are correct in your camera instead of having to spend time fixing it later in Photoshop or some other photo editing software!
Don't forget about etiquette- hand written thank you notes go a long way.
Never stop learning.
So, what's the best business or photography advice YOU have received?