1) The document provides step-by-step instructions for getting started with Diigo, an online bookmarking and annotation tool. It explains how to create an account, install the Diigo toolbar, bookmark and highlight web pages, add sticky notes, capture images, and create a user group.
2) Key steps include creating an account on the Diigo website, installing the browser toolbar, bookmarking and tagging web pages from the toolbar, highlighting text and viewing annotations in the Diigo library, and inviting friends to join a user-created group for collaboration.
3) Features covered are bookmarking, highlighting, adding sticky notes to pages or highlights, hiding public notes, capturing screenshots, and forming a group