Cutting a dine style mouth in it

On the position I indicated do I want a dino style mount. So I want to cute it open on the line indicated and move it a little upward so I get a real dino mouth. Once that is done would I only need to do a couple extrudes and fills to finish it but I don’t know how to cut it open.

To cut open the edge you have selected press V.

thank you :slight_smile: