How to Learn Category Theory

I always find it helpful if even if it's just kind of in the category of Haskell functions and types that you can suddenly see these ideas come to life. Things like product, coproduct, functor, natural transformation, all the stuff can be implemented. And you see it, you can touch it with your hands, right? But one thing that I would like to tell everybody who's trying to learn category theory is not to give up because it is hard.