How to change from a DPM (Display Parent Model) to a DCM (Display Child Model)

Hi,

I have sporting goods with 2 variations in terms of style. I would like each variation to have there own title, as they are quite different - however, it looks like due to it being in the category ‘sports’ and `style’ variation it is automatically in the DPM (Display Parent Model).
In the editor (back end) the both titels are different, but in the front end listing the titles are the same.

I would like to change it to DCM (Display Child Model) so it will show the size in each child listing. Do you know if this is possible? and how to do this?
Many thanks in advance