If your cat has never worn a cat harness or a cat collar it may be a slow transition for your kitty so please be patient. Please evaluate inside your home before your big adventure! Test to make sure you have purchased the correct size and that if you were to try get your cats elbow to wiggle out, that this won't be possible. Their elbows should not be able to wiggle out of it if there is only that minimal of space. To fasten your cat harness properly, there should be only enough room for a finger gap between the cats body and the harness. If you do not have one, you can use a piece of string or fabric then measure it up against a ruler. The easiest way to measure your cats neck and chest circumference is with a soft tape measure. Ensure it is a snug fit, not too tight and not too loose. Our velcro adjustable cat harness is easy to put on simple adjust the chest strap first then the neck strap with their front legs in between. Having the correct size will prevent the cat from escaping. To fit our Catventure Cat Harness, start by measuring your cat and comparing with our sizing chart below.