If you're doing a tattoo with brown shading, vs. solid brown - i've found it helpful to mix opposite colors on the color wheel. You get way more tone in it- try mixing like lavender and yellow, primary blue and orange, green and red- etc.The result isn't really a true brown, but it definitely gives you a lot more range than just a straight brown. For a true brown - try chocolate or coco or something i think it's called by Starbrite. It's a really good middle brown, it's horrible for mixing - but it goes in the skin well and is a good deep primary brown. If you cut it with a little water or alchohol/glycerine mix, it's good for shading out areas too.