There is a technique, that is not that dissimilar to climbing. You have to learn how to grip it so that when your hand closes it is in the strongest position. Try using the other hand to assist with the close, slowly release and see what position your hand ends up in.
I have tiny hands, so barely have my back two on at the start. If i turn the CoC slightly in my hand, I can get my back two on, but this leaves my hand in a weak position for actually closing it.
Just experiment a bit, but don't explode your hand
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have just put my CoC in my hand and have remembered exactly how it likes being held.
Turn your hand so that the edge of it is facing you with your thumb and index finger forming a V.
Slide one handle of the CoC tightly down into the bottom of the V (using your other hand) and then reach your fingers around the other handle. The most important part is to use the other hand to keep the first handle down in the bottom of the V whilst you are reaching around with your fingers and starting to squeeze. This will prevent the CoC from rotating into a position where you are trying to close it between your fingers and thumb, rather than fingers and palm.
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