To create a portfolio, first create a page, (you can name this portfolio, or whatever you want). Then select the portfolio template on the right.
Next go to your Genesis Theme Settings page – http://www.yoursite.com/wp-admin/admin.php?page=genesis. If you scroll near the bottom of the page you will see “Portfolio Page Settings”. This is where you can configure the settings for your portfolio.
You can also create multiple portfolio pages based on categories as well. Take a look here – http://appfinite.com/topic/different-portfolio-with-different-categories/