How Do I Do That in Photoshop?

Draw a Free-Form Path?

If you want to create a free-form path that you draw like you’re using the Lasso tool, there’s a special Pen tool just for that. It's called the Freeform Pen tool, and it's nested with the Pen tool (its icon looks like the Pen tool, but with a little “S” coming out of the end of the pen tip). To use it, just start tracing along the edge of the object you want to select and, as you draw, it automatically lays down the points for you. Once your path is done (you’ve connected the final point with the point you started with), ...