Equipment Screen Display

I’m coding an Equipment screen GUI and so far i’m having problems with square one. my script should display a button on the screen when the “e” key is pressed however it is not doing this.

using UnityEngine;
using System.Collections;

public class Equipment : MonoBehaviour
{	
	public string Kill = "";
	
	void OnGUI()
	{
		Display();
	}
	
	void Display()
	{
		if(Input.GetKeyDown("e"))
		{
			GUI.Button(new Rect(200, 200, 200, 200), Kill);
		}

	}
}

Try using if(Input.GetKey(“e”)) instead of if(Input.GetKeyDown(“e”)).