You can check this documentation page and see if you feel like you can manage the export yourself (it's pretty easy), or if you need a guided transfer:
I'm happy to talk you through the steps as well :)
*Go to Dashboard > Tools
*Your site will export as an XML file
*Save this as an XML file to your desktop (or wherever it will be handy)
*Go to your new .org site, and go to Tools > Import, and select this file.
*It will upload, and you should be all set there!
Do not deactivate your WordPress.com blog before everything transfers over. After everything has transferred to your satisfaction, you can safely deactivate your blog (or just set it to "private").
Can you let me know of your WordPress.com blog so I can transfer the email subscribers?