Skull Crusher(the proper way of executing)

[hercules]

i'm just a beginner in this workout "SKULL CRUSHER'', all i wan't is your tips on how to do this in a proper way and how many times should i work for this?
thank's Guy's.

[Psycoswole]

I rotate skull crushers and above the head tri extensions each time i work tri's. Lay flat extend your arms srtaight out (common grip is close but you can use different grips to target diff tri heads).Bring the weight down towards your forehead keeping your elbows in the same spot, and extend. You can do these with a variety of set/rep schemes.

[Red Ketchup]

Check out the animated GIF on this page:

http://www.bodybuilding.com/fun/triceps2.htm

They call it "Lying Barbell Triceps Extensions".

Red