Split Segmentation will not be turned on for any account by default. If you would like to request this feature please send a request to your CSM or support.
Once the feature has been enabled:
Split Segmentation will add a new Clause when building Segments named "Split".
**We have made a recent update to Split Segments. Before, you could select 100% of the recipients, sending it out as a full A/B split mailing. Now however, we don't allow entering 100% when distributing to a percentage of the segment. Instead, you will see a message that populates you to select a percent between 1-99, which will then allow you to send a winner mailing.
However, if you are needing to be able to send fully as an A/B mailing to all recipients, we can recommend using the split segmentation. This allows you to create a segment and divide it into however many parts needed.
In your segment, there should be a new clause called: Split -- please select this clause.
Next, assign however many groups this should have.
Select which group this segment should pull.
When you are ready to create the segment for the next group, simply copy the first segment and change the group criteria.
When creating the mailings, Instead of a Split Test mailing, please select Regular. Then assign the 1st mailing to the 1st Split segment, then the 2nd mailing to the 2nd segment, etc.
Please see a quick video here demonstrating these steps: https://www.screencast.com/t/ZRdViThGK7Sw