The generator has the ability to fetch several sample template themes from this repository in addition to the bundled "default" one, which will help you creating a nice looking paginator.
rails g kaminari:views default
You can also specify between erb, haml or slim (in some themes):
rails g kaminari:views semantic_ui -e haml
To see the full list of avaliable themes, take a look at the themes repository, or just hit the generator without specifying THEME argument.
rails g kaminari:views