It's a personal thing that you need to learn to embrace, and then try to explain. In the end it's all about being entertained. Did it entertain you? What about it entertained you?

Liking a film is often a gut-feeling. You probably like something before you can actually pinpoint why exactly. Take some time after a viewing to reflect on what you liked, which specific scene or moment, and what you felt exactly. There is still a grey-area where you might appreciate certain aspects of a film, but they fell short in some way.

Don't "ignore" other opinions. There is nothing wrong with being 'influenced' by other opinions. They can often teach you different insights. And if you really, really like something, you'll stick to that opinion no matter what. Ignore random user-reviews? Maybe. But if someone can explain to you in earnest why they dislike or like something and you'll agree with them, then there is nothing wrong with that.

I'd rather say that you'd read or watch critics who review movies from an honest and knowledgable perspective that can explain their opinions. They don't even have to be people you agree to about a film. Watch deconstructions. In-depth reviews. Honest takes on movies.

You'll learn how to express yourself about films that way and eventually really hone in on what you like. Which will change over time, and there is nothing wrong with that. But it's all about being entertained.