You most likely did a push-up at some stage in your life before beginning CrossFit, but you may not have done the full spectrum of motion pushups we use in CrossFit. Your arms should be absolutely straight at the top, and your chest should be in touch with the ground at the bottom.
To the tune of the song "Flower" perform the following movements for every mention of: Bring Sally Up: Hold top of the Push-Up Bring Sally Down: Hold the bottom of the Push-Up (keep chest 1 in off the ground)