During your time as a student, you'll have lots of different kinds of experiences, all of which will contribute to your own personal development.
To record that development as part of your e-portfolio, I recommend you setup a blog to keep a record of your thoughts and reflections, ideas and new bits of knowledge gained from the various experinces you are have.
Although there are many blogging platforms you can use, the one I recommend you use for your portfolio blog is Google Blogger - the reason for this is that although Google sites comes with it's own online journal tool, it's not as powerful or as flexible to use as Blogger (plus there's a great free smartphone app you can download for iOS and android which means you can blog on the go!).
Getting started with Blogger
Getting started with reflective writing
If you've never written a reflective piece before it can seem quite daunting, the link below will take you to a guide which walks you through the process:
Examples of Reflective Blogs