Image Effect in unity Free

ok…so i want to have images (semi - transparent) to appear in the players gui…where ever they go i want the image to appear

Try with this shader:

Shader "Custom/UnlitOverlayTransparent" {
Properties {
    _MainTex ("Base (RGB) Trans ", 2D) = "white" {}
}
  
SubShader {
    Tags {"Queue"="Overlay" "IgnoreProjector"="True" "RenderType"="Overlay"}
    LOD 100
    
    ZTest Always
  
    Pass {
        SetTexture [_MainTex] { combine texture } 
    }
}
}