Use the Hot Process method
Split the soap batter in 3:
Color 2/3 with Turmeric
Split the rest into two parts, where one is significantly bigger.
Leave the small part un-colored and ad Cocoa Powder to the other
Fill the bottom of the mold with yellow soap. Make sure to tap out the air after each scoop
Ad the uncolored soap in the middle in a stripe
Place the brown and yellow batter on each side of the un-colored
Top up with the rest of your batter but imagine one side is yellow, and one is brown
Swirl the batter once, starting in the far end and middle of the mold, and keep rotating the spoon while dragging it slowly thru to the other end of the mold