Changing Font, Background/Style of GUI Buttons

Hello Everyone! I am working on my Main Menu for my RPG Game and i have made 3 GUI Buttons, All three buttons work and they are in the correct position and correct size. However they are dull and boring and I really want to change the font, background or style of GUI. I want the background to be behind the text so the user can still see the text of the GUI Button. I have tried many tutorials on how to do this but i get confused on how to create the Texture, How to import it into my scene/project and then how to make it the background of my GUI button. I have found many tutorials however most of them are C# when I don't use that and I do not understand it either, So I use Javascript. Here is my Main Menu so far: var MainMenuScene: String;

 function OnGUI(){
 
 if(GUI.Button(Rect(Screen.width /2 - 100,Screen.height /2 - 50,250,50), "Main Menu")){
             Application.LoadLevel(MainMenuScene);
             Debug.Log("Game Started!");
         }
         
         //Make Change Graphics Quality button
             if(GUI.Button(Rect(Screen.width /2 - 100,Screen.height /2 ,250,50), "Options")){
             Application.LoadLevel(MainMenuScene);
             Debug.Log("Options: Loaded");
         }
         
         //Make quit game button
         if (GUI.Button (Rect (Screen.width /2 - 100,Screen.height /2 + 50,250,50), "Quit Game")){
             Application.Quit();
             Debug.Log("Game Closed!");
         }
     }

If anyone can tell me how i would add a texture to that then please tell me and I would very appreciate it. Also could you tell me how i would make the texture in Photoshop and how i would import it into Unity such as how big the texture would be to fit the GUI Button.

Thanks in advanced

UniqueProductionZ

P.S - I'm sorry for asking a rubbish newbie question, I'm new to Unity.