Do you want to attract millennial's? Oh yeah. A couple years ago hi Inc. predicted that millennial's "will soon be the biggest bookers of hotel rooms in the world," citing a Forbes study finding that "by 2020 millennial's will be taking 320 million international trips per year, making them the biggest travel market on the planet."
So how to attract them? First, ensure that your website is as mobile-friendly as possible. Millennial's looooove their mobile devices, and if they can't interact with you easily that way, they're not likely to keep trying.
A mobile-friendly hotel site is one that does not use small, hard-to-read text and does not pack the site with unnecessarily large images that take forever to load -- slow loads aggravate millennial's to no end and drive them away.
In fact, text on a good mobile site is just bare minimum. There are no long, flowery descriptions, just enough text to explain what the user needs to know now.
A good mobile site is simple and quick to navigate, which means losing those tiny links that are really hard to click. It means offering pages that come to the end of the scroll pretty quickly (really attractive sites have practically zero scrolling required), and you don't have to pinch and zoom to read it.
On hotel websites that attract millennial's Adobe Flash is used minimally if at all, and pop-ups are few. Google Maps is integrated into the site so they can hit a link and get directions to your hotel.
Above all a mobile-friendly site gives users a way to cut to the chase and just contact you quickly -- there's a large, obvious, easy to hit button that calls you. And it's a good idea to make your logo a link that can always return the user to the home page as well.
If you have to hire a designer to get all that, it's worth the cost.