Keeping organized notes is one of the most important aspects of researching your genealogy. As you go back in time, more ancestors will appear, family lines will branch off, and you'll need to keep more documents as you comb through archives. Organizing will also give you a sense of what information you're missing. Where are the holes? What information are you sure about, and what's still uncertain?
To get started, there are a few free online tools that can help keep your data together. One is Family Echo, which allows you to draw and maintain a family tree online, keeping it organized along the way. FamilySearch also has an excellent suite of tools for building and maintaining a family tree, as well as the ability to upload scanned photographs and documentation.
Even if you keep records online as master copies (and for other family members to view), some of the work is going to be done by hand. The BBC keeps a set of useful blank documents including a template for taking notes as you find out about new ancestors. The National Archives also has a set of blank documentation for every U.S. census between 1790 and 1940 (census records are released 72 years after they are taken). If you've ever tried to read a 200-year-old census log, you'll appreciate how nice it is to have a clean copy for reference.
Once you start collecting documents, it's going to be important to preserve them carefully. Most family papers can be left alone in a cool, dry environment, but old photographs often need special care. Choose an album with plastic pockets or non-acidic paper. Do not use tape or glue to attach your valuable photos or put them in self-stick albums [source: National Archives].
Finally, don't just keep track of what you find; keep track of where you found it. This genealogical work you're doing, especially if you've done it accurately, is going to be of use not only to you but also to your descendants. Any extra clues you can give them to confirm your story will be helpful.