Switzerland Purchase

Hello all.......I want to purchase a timepiece in Switzerland, for the experience. I understand it's not financially the most prudent, but it will add to the enjoyment of owning the watch. My question.....as a U.S. citizen, what will the bottom line look like? How much more will it cost, all in? I understand the euro, or CHF vs dollar component, I've traveled to Europe, but never purchased a high dollar item. How does the tax work, customs, etc....I'm not comfortable just wearing the watch home, without declaring, that's just the way I am. Thanks for the help!