Sign up for a free Mendeley account on the Mendeley Homepage. You can start using Mendeley Web without any installation.
For Mendeley Desktop, download the free software from Mendeley website. The free version gives you 2GB of personal library space. You can upgrade to a paid plan for more storage.
Install the Mendeley Web Importer to your web browser to import references and documents easily. Available for major web browsers.
To get the Mendeley Citation Plugin to insert citation in Microsoft Word (Windows and Mac), go to Mendeley Desktop. Select Tools > Install MS Word Plugin.
Mendeley is a free reference manager and academic social network that can help you organize your research, collaborate with others online, and discover the latest research.
Mendeley Desktop is available on Mac, Windows and Linux. The web version, Mendeley Web, works on all major browsers.
For more video tutorials, go to the Mendeley YouTube Channel.
Besides Mendeley, there are other Bibliographic/Citation Management Software (BMS), like EndNote and Zotero.