Hey, I have a little something I wanna say.
That's cool, what is it?
I really don't know how to express what I want to say.
I think you should get whatever it is off your chest. Feel free to express yourself however you want.
I'm scared what you'll think about me after I say it.
You can express your opinion about things if you want. you don't have to consider how it will appear, just don't be harmful about it. It's good to be open and honest about how you feel about things.