There is no definitive answer to this question, as you can use any colors you like when drawing Patrick. However, he is usually shown with a green body and a pink head. You might also want to experiment with different color combinations to see what looks best. For example, you could try using a light green for the body and dark green for the head, or vice versa. You could also use different shades of pink for the head, or even add some other colors into the mix.