Here is how:
Step 1 download ibis paint
Step 2 find any image on Google or any sprite website
Step 3 if you found a perfect image use the bucket tool
Step 4 use the eraser icon on the bucket if ur using it
Step 5 turn on gap recognition
Step 6 remove any color and download the colors and also make them transparent Step 7 keep downloading other colors
Step 8 go to castle and merge the layers using image
Final Step your done!