You can straightforwardly use cute animals in advertising about cute animals, and rely on that. For instance, sloths:
Or you can go meta, and use cute animals in advertising to comment on advertising. For instance, cats:
Or you can take drugs. Turtles:
In truth probably none of these are mutually exclusive.
References:
* Is This the Cutest Ad Ever in the Entire World? Yes [AdAge]
* New Jolly Rancher commercial features a talking, flying turtle with laser eyes. [Copyranter]
* Catvertising: The Advertising Strategy That Is Going To Change Everything (VIDEO) [HuffPo]