Change GUILayout.Button fontsize

I have two buttons on scene. First button i need to transparent, no need like button. But start button also displaying same thing. How to change the fontsize of button.

 void OnGUI() {
         
         GUI.skin.label = style;
         GUILayout.Label("1. Print the alphabet image targets located at", style);
         
         GUI.skin.button = btnstyle;
         if(GUILayout.Button("www.url.net", btnstyle)){
             
             
             Application.OpenURL("http://www.url.net");
             
         }
         
         
         GUI.skin.label = style1;
         GUILayout.Label("2. Point any of the animal images", style1);
         
         GUI.skin.label = style2;
         GUILayout.Label("3. Finally your kids able to see the 3D animal render on ", style2);
         
         
         GUI.skin.label = style3;
         GUILayout.Label("the screen with sounds", style3);
         
         GUI.skin.button = startbtnstyle;
         
         GUI.skin.button.fontSize= 50;
         
         if(GUILayout.Button("Start", startbtnstyle)){
             
             
              Application.LoadLevel("testt");
             
         
             
             
             
         }
         
         
     }