Patience
Well, okay. This one is pretty lame. But still, quite important.
If you launch into a new website thinking you'll be driving tons of traffic in a week or even a month, you're probably delusional.
Of course, you might get lucky. You might get a page one link on the New York Times website, or get a 15 minute chat up on The Today Show. If you can't manage a coup of that caliber, well, you better plan for alonger-term campaign.
Not only does it take search spiders time to find, catalog, and rank your web pages, but some of the engines are even known to actively discriminate against new domains. If you are lucky enough to be working with an established domain—particularly if it has an existing collection of backlinks—your time in the waiting room will probably be less. But if your domain is new, count on 6 months to a year of lead time. No kidding. You can, and should, use that time to shore up your backlinks, add content, and do the million other things that webmasters should be doing. If you need traffic to survive, you should consider a Paid Search campaign, such as Google Adwords.