Force Specific Variations
All you need to do is grab the ID of both the experiment and also the variation that you want to force. You can do that as explained in this article.
After you have the two IDs handy you can build the query variable that needs to be added to the experiment URL:
_conv_eforce=[experiment_id].[variation_id] where [experiment_id] and [variation_id] will be replaced with actual values.
Example: http://www.mysite.com/test-page.html?_conv_eforce=123.678 where 123 is the experiment ID and 678 is the variation ID.
When forcing a variation, you must still match the Site Area and Audience conditions for this to work properly.