There are Many great tutorials and videos out there to teach you how to use pinterest.
Basically you request an invitation to pinterest and then you create your account, load the pin it to your bookmarks menu and start pinning. You can create boards for topic you want to accumulate ideas for. The best part is the pins show the picture of the idea you want to keep track of AND the weblink/address where the pin is from is on the board as well! So you can always go back to the idea.
You can also browse other boards people have created and repin the ideas they have found for your own boards.
This is soooo very much better than just bookmarking a site and then forgetting where you marked it!
Here is a link to some of the boards I have created so far!
If you want an invite to pinterest just leave me a comment and I will invite you!