need help modeling a head.

ok im working on a low poly head for a game of mine. and well i started out with a full head then i started working on one side making it look better and better then after a while one side look a whole lot better. So what i did was deleted the half side of the face that i didnt like. So now how can i copy the side i like the most and horzontaly flip it the other way so it looks like a nice looking head?

use a mirror modifier, and then when u’re done modeling u can apply it.

uh… i never used that before or even no where that is located lol.

its located in the modifiers section in the editing section.JUst press the drop down and select mirror.And choose your axis on which it should act upon.Here is a screen shot.

wow thanks a bunch