Setting up Products with Variants and Options

The process for setting up variants is actually pretty straightforward:

1. In Products > Taxonomy > Options, create the options you want to offer for the product (e.g. Color, Size, Size Type).
    
2. Create the choices for each option (e.g. for Color, create Black, Navy Blue, OD Green, and Coyote Tan.  If you want the choices to appear in a particular order, specify the Sort order as well.  Lowest appears first.  If the sort order is the same, the choices will be sorted alphabetically)
    
3. In Products > Taxonomy > Groups, create a group for the products that have these options (e.g. Safe Life Defense Vests). You can enter a description and detailed description, and then select the Options you created above. Note that the order of the options in the selection box matters. They will appear in that order on the product page (e.g. Color, Size, Size Type)
    
4. In Products > Products > Products, create the product variants that you want to offer for sale. It will be easiest to create one of them exactly how you want it and then use the Duplicate button to create copies. There is no requirement to the product code or SKU, but for ease of use, it is recommended to add the option choices to the end of the product code (e.g. if the product is SLD-IIIA-TAC, SLD-IIIA-TAC-B-L-R would be SLD-IIIA-TAC Black Large Regular and SLD-IIIA-TAC-G-XS-S would be SLD-IIIA-TAC OD Green Extra Small Short). Note that it is not necessary to create every possible product variant if you do not plan to stock all of them. For unusual sizes, it would be much easier to create a special order product using Product Addons. Note that you may also want to remove the word "Copy" from each of the duplicate Product Titles so that these don't show up to the customer when they make a selection. Additionally, if you don't want each of the product variants to show up in search results, you will want to check the "not searchable" flag in the details tab of a product.
5. In Products > Taxonomy > Group Variants, add a new variant for each product you just created. You will select the Product Group you created (e.g. Safe Life Defense Vests), a product, by typing the product code and pressing the Tab key to select it, and then the Product options that will select that product.
    
6. You can then view these product variants via your front-end site.  You will see a series of dropdown lists which will allow you to select the product based on the option choices.

Additional Recommendations

If you made all your product variants "Not searchable" make sure to uncheck this box from ONE of the variants so that it can be the "default" product.