You have a couple of options with this one, the easiest of which is tuning your style within individual registrations. With Yamaha keyboards, this is done via the Mixing Console, where you can increase the drum volume(s), change the EQs, and a number of other parameters that will make those drums come alive. This can then be saved to the registration(s) for that particular song. Be sure the Style Box is ticked in the Registration Memory Contents page and don't forget to save the Registration Bank as well as the individual registration.

The second Yamaha option is to use the onboard Style Creator program and perform the same tuning technique(s), then rename and save the style as a User Style. This technique allows you to access the file without going through the registration(s).

Both techniques work quite well.

Cheers,

Gary