Illustrator has a scissors tool to cut a gap into a path, but Photoshop doesn’t have this tool unfortunately… But there is a simple way around this!
Simply select the pen tool and carefully create three new points in your path where you want to create your break in the path. I say carefully as it is easy to create a point and drag it a little, altering your carefully drawn path.
Next, simply select the middle point out of the three you have created and hit the Delete key and there you go - how to cut a gap in a path without the scissors tool… Baaahh, who needs scissors when you are a Photoshop Ninja!