When you are using a ceramic sharpener to sharpen a knife you have to start with the base of the knife and slide the knife down the length of the sharpener. When you do this just apply little pressure so that the knife slides on the sharpener and the cutting edge grazes the sharpener. The angle at which you slide the knife should be constant during every stroke. You have to end a stroke with the tip of the knife at the base of the sharpener. Repeat this step on the other side of the blade.