Mendeley allows you to import citations and bibliographic information directly in to your Word document. (See installing the Word plug in).
Depending on whether you're working on a Mac or Windows computer the location and look of the Mendeley plugin will be slightly different, though the functionality is the same.
Creating a bibliography in Mendeley is easy. Once you've inserted a citation in to your paper Mendeley will keep a running tally of the resources you've used. You can insert the bibliography at any time. If you add more citations Mendeley will automatically update your bibliography. To insert the bibliography simply click the Insert Bibliography button in the plugin menu.