The invisible decrease is often used in amigurumi and other crochet projects where a smooth and seamless appearance is desired. It creates a decrease that is less noticeable and does not leave a hole or gap in the fabric. The sticth reated looks very similar to the other regular stitches.
Insert your hook through the front loop of the first sc.
Without yarning over, insert your hook through the front loop of the next sc. You should have three loops on your hook.
Yarn over and pull through the first 2 loops on your hook.
Look after step 3
Yarn over and putt through both loops on your hook.