Our newest generation of the Garlic Twister is now more ergonomic with improved grip. If you tend to still find it difficult, here are a couple tips:
1) Crush the garlic beforehand by giving it a whack with the Garlic Twister a couple times.
2) Work your way down. Don't completely close until you have start mincing.
Please contact us if you have any more difficulty. We'd be very happy to help you, as we use this ourselves daily!