Breaking ball won't break without snapping wrist

I can throw a decent slurvish pitch but I can only do it if I snap the wrist which I know is wrong. I have tried to just throw it kinda like a football but it doesn’t break at all. Any tips?

And it probably tends to stay high, right?
Let’s go over it from the beginning. The slider grip is very much offcenter, with the index and middle fingers very close together and on the smooth surface of the ball, middle finger just touching one seam, fourth and fifth fingers curled up together on the side of the ball, thumb underneath on one seam for support. You throw it like a curve, but you DON’T snap your wrist; you just turn it over (slight pronation), kind of like a chef flipping a pancake or a crepe. And it usually works best when you throw it sidearm—you might consider that.
When I threw my curve I used a sharp karate-chop wrist snap, so when I was learning the slider I had to ease up on it. Let me tell you, like Rome the slider wasn’t built in a day; I spent some months working with it before I felt comfortable enough with it that I could use it in a game. But once I had it, it became my strikeout pitch. So hang in there; eventually you’ll get it. 8)