make a new layer by going to layer> new layer
take the pen tool, it should look like this:
Set the setting to this**:
use the pen tool an make a curvy path like this:
Click on the brush tol and set it to 5px or 7px depending on how big the picture is.
The brush should be a circle.
click back on the pen tool and right click on the path, select stroke path.
make sure it says Brush, also check the box next to Simulate Pressure
press ok, and then right click on the path and delete it
it should look like this so far:
now right click on the layer with the beam, select blending options, and set them to this**:
press ok
now zoom in and use the erase tool and erase every other line so it looks like this:
merge layers and now your done!!!
**right click on the image and select view image to see the full size