How to make my collectables appear on my screen

I kind of needed the same for an inventory in my game. I created an array where I store the names of the objects that I grabbed. Although if you only want to show the images, you probably don't need that. Once you pickup an item the object gets destroyed, and it has to show the icon on screen.

Basically what I did was something in the lines of this:

 var show : boolean; //display image, yes or no
 var icon : Texture2D; //define the image icon (set in inspector)
 var posX : int; //define the X position of the image
 var posY : int; //define the Y position of the image
 posX = 14; //set the X position
 posY = 13; //set the Y position
 
 function Start() {
     //You don't have the item at start, so don't display the image
     show = false;
 }
 
 function OnGUI () {
     if(show){
         //If item is obtained, show the icon on the screen.
         GUI.depth = 80;
         GUI.DrawTexture(new Rect(Screen.width / 2 - posX,Screen.height - posY,40,39), icon);
     }
 }

Just set show on true once you click on the object.