To effectively market what you have, you must be able to see it clearly.
It's one thing to try and "spin" the public, it's another thing to try and spin yourself. You must be able to see the flaws in the work. You have to be able to understand the barriers that separate people from the work.
Those barriers could be a misunderstanding of the work itself. It could be price. It could be difficulty finding parking. What's important is that you understand that those barriers exist AND that you do whatever you can to reduce those barriers.
Whenever I'm marketing art the first thing I do is take a step back and identify the problems. It is one of the few times that I err on the side of being cynical. In fact, I can be a bit harsh. But it's a necessary step. If I see the problems they I can create marketing that helps to deal with the problems.
If the art has the potential to be confusing, I can provide content.
If price is a barrier I can try to work out a sale that balances our need for revenue with the need for access.
You get the idea.
The key is the willingness to see the problems.