It's all about getting a lot of knowledgeable people here. There are two ways to get more knowledgeable people here:
1) Find more knowledgeable people and tell them to come here
2) Make this site awesome so that when they do come here, they stay
Both #1 and #2 are necessary, but the truth is, enough people will be passing through this site, even accidentally, so anything you can do to make them STICK by making this site terrific will help.
Here are ways to make this site awesome:
Edit question titles to be clear, complete sentences, so that the home page looks more interesting, not like a list of keywords.
Edit question text for grammar, spelling, and clarity. Just improving the English quality will dramatically improve people's perceptions of the quality of this site.
Add the occasional picture or photograph to questions and answers. Don't go crazy, with random pictures of beaches that you have to scroll past, but if you see a question about how to get out of Ulan Bator, include a smallish (300x200) snapshot showing you and your friends in front of the Yak market. (Do they even have a yak market)?
Overkill the questions that you do answer. When somebody asks about how long they should allow for a connection in JFK, write an essay about minimum connection times. Not just an essay, an EPIC essay. The CANONICAL internet reference on minimum connection times. These longer, overkill answers get linked and get page views and make people know about the site.
Ask more questions! We already have a 96% answer rate here. That means there are people sitting around just waiting to answer more questions. Don't ask fake questions, but every time you have a real question in travel or travel planning, think about how many other people will probably have the same question, so type it in before you start your internet research project, then, if nobody else answers it, answer it yourself. (Don't take this too far... don't ask questions that are already trivially answerable with a simple Google search. We don't need to add to the duplication. But if you can come up with questions that other people might have where Google results are thin or confusing, definitely ask.)
This goes a lot way to making the site great, which will make far more of the visitors who land here accidentally come back again.