To change your Catch The Beat character:
-Open your osu! skin folder. The default file path is (C:/Program Files/osu!/Skins)
-Select your current active skin
-Choose a replacement CtB character from this thread that you wish to use
-Right click the image, select "Save Image As.." and save it as "fruit-ryuuta" somewhere easily accessible (Desktop, My Documents)
-Drag the new character into the Skin folder which you should already have open. Click "Yes" to replace the old version if prompted.
Below we have:
Riven. Orianna. Vladimir. Syndra. Poros. Lolipoppy. Urgot. Nami. Ahri. Popstar Ahri. (more to come soon!)
xD