So I defined product types and default specifications already and was told to export some items, edit the values/add some more items and import them back. I noticed that the exported table gives each specification its own field. Though I didn't need to add more specifications at that point, I would imagine you could add more specifications by following the same field format shown ( SpecGroup > SpecName ). I added a few more rows of items and imported the products through the admin interface. After you upload the .CSV file, you'll need to map your CSV column with the appropriate database column. Make sure to assign each of your spec fields to the specification database column.
This worked great for me
The post by wazoodle in this thread is also helpful about creating specs:
http://www.viart.com/custom_product_fields.html