Defining a starting position for a gameobject?

Im a total noob to programming and im having issues. I want my object to start at 0,0,0 (xyz) position when the game begins and i cant find out how to do this. So far this is what ive got but when i press the play button nothing happens and the object does not appear in the center of the screen. Any help?

public class Movement : MonoBehaviour {
        public GameObject snakeHead;
    	// Use this for initialization
    	void Start ()
            snakeHead.transform.position = new Vector3(0, 0, 0);

0,0,0 is in worldspace, if the camera was moved, then the object will not be in the center of the screen. Did you setup a GameObject to snakehead in the inspector?

Should watch many of the tutorials, they cover all of the essentials to know: Unity Tutorials