ProGuard - How to keep methods and obfuscate them at the same time?

I am trying to manually obfuscate my Android application (yes, I know, it's a pain) and for that I need to keep all the methods I implement yet also obfuscate them with ProGuard at the same time.

I have tried changing the config like this:

-keep class com.project.x.* {

}

But it kept all the class names and method names and still removed my unused code.

What can I do to solve this issue?

Thanks in advance!