My way is a bit different but it works well when you have a large tank full of rock and coral.
Take a piece of clear lexan that is just about the width of your tank and lower it into the water.
With your net start to herd the fish of choice towards the clear lexan.
When he hits it get ready to scoop.
I know it sounds funny but the fish can't see it when it's submerged and they are usually so stunned they just sit there for a while trying to figure it out.
I've caught a bunch of my fish this way when moving to different tanks.
