Cameron Moll’s Eight things I wish I’d known when I started is great advice.
But the sooner you and I learn to communicate with our designs using only what’s necessary and relevant, rather than decorate for the mere purpose of decorating, the sooner we’ll find our designs touch the consumer’s heart, rather than just satisfy the designer’s eye. Think of it this way: Every element added to a design, whether print or web, decreases the importance of every other element already on the page. You better be sure, then, that the additional element enhances rather than detracts.
Also great are the points on perfecting details until it stops being cost-effective.