There is a good example on my site: http://www.codefleet.net/cyclone-slider-2/templates/lea/
Click on the 7th slide with the pictures of wildebeest. As you can see I added a text-align:center on the image containing element:
and similar to Chad Warner's comment above, add margin: 0 auto. BUT, adding !important is considered bad practice, so just make your style more specific (you can google that).
Note, you have to change
.cycloneslider-template-lea to the class name of your template.