When raising the lid, lift straight up first, then tilt back . If you encounter any resistance, simply grab the base of the unit with one hand and use your other hand to lift the cover. With use, the lid mechanism will smooth out considerably. Remember, don't press down too hard on the cover. You only need to use enough force to gently but firmly hold the bagel in place.
Excessive pressure traps the knife blade.
When pressing the lid down, place the ball your thumb in one of the depressions and your fingers in the other. This properly positions your hand for stability while slicing and keeps your fingers away from the knife for added safety. When cutting, use short, rapid strokes and let the knife do its job. As you experiment with different types of bagels, croissants, rolls, etc., you will develop your own feel and technique.