Be especially careful when adapting paper brochures for an online site. Keep your pages clean. Do not overload with graphics and multimedia effects.
Speed is vital.
Casual visitors will leave rather than wait for a minute to see your page download. Make sure your site is easy to navigate. Provide a site map, and a search engine if the site is very big. If what they want is not available in a few clicks they will look elsewhere. Don't market to individuals, market to groups.