Add Artwork instruction to README.md (#1066)

* Add Artwork instruction to README.md

* Update README.md

---------

Co-authored-by: dborth <[email protected]>

README.md

@@ -43,6 +43,7 @@ Wii homebrew is WiiBrew (www.wiibrew.org).
 * Retrode/Xbox 360/Hornet controller support
 * SNES Superscope, Mouse, Justifier support
 * Cheat support
+* Artwork (artwork, cover or screenshot) support
 * Satellaview (BS-X) support
 * Auto Load/Save Game Snapshots and SRAM
 * Custom controller configurations
@@ -870,6 +871,15 @@ the Sound Effects Volume. The Exit Action can be set to "Return to Loader",
 to Vertical or Horizontal and then you can increase and decrease the Music
 and Sound Effects Volume.
 
+### ARTWORK
+
+Artwork, covers or screenshots will be displayed on the main menu when
+each game is selected. Select which type to display on the menu by going
+to Settings > Menu > Preview Image. Each image resides in the respectively
+named folder (eg: sd:/snes9xgx/covers). They should be a PNG named exactly 
+the same as as the rom and sized no more than 640px by 480px. Recommendend 
+format is 316px x 224px PNG with a 32bit depth.
+
 ### NETWORK
 
 If you're going to be using your Network (LAN) to load and/or save from you