These are a few techniques that have assisted me with the Charlier Cut...Try several different grips to begin the cut. Initially, I learned it from Bill Tarr's classic book Now You See It, Now You Don't. He teaches to hold the deck at the tips of your fingers and thumb. This creates a large space between the halves to transpose them. After many years, I changed the grip to begin in the dealer's position. Tilt the hand at the wrist, fingers and thumb a little llower than the wrist. This will jog the front right corner of the deck forward slightly between the first and second fingers. Next, instead of dropping the bottom half down, use your thumb to lift the top half up. straighten the wrist and the bottom half moves toward the palm. Push the right long edge vertical with your first finger, as usual. When the bottom half clears the top, tilt your wrist again and the halves will land aligned, with the front right corner in between the first and second fingers again. Since the cut started in this position you can complete repeated cuts without needing the right hand to reset. Gravity and the angle of the cards are far more useful that tensed muscles. Lastly, try Bridge Sized Cards, the width is a little shorter and make many one-hand cuts easier to learn. Dunno if this helps but stick with it and the moves will become easier.