How do I add a gem to my project and actually see the visual difference it makes?

I feel as if I am missing something very obvious here. I have searched for days on how to add gems to my ruby on rails project. So far, the furthest I have gotten is installing the gem and using bundle install, but how do I actually implement it into my website project? The specific gem I am looking at using is a Carousel image slider called Slick. It slides one by one to another image and allows the user to also click one of two buttons to go back or forward to another image. I downloaded the slick file and I clearly see that it has a good bit of coding in it. Am I supposed to drag that file into a specific folder in my rails project directory? Please Help!