The koozie colors for neoprene range from camo to hot pink or if you are feeling extra daring try going with Brown. The brown koozie does not get enough credit. The always come out very nice and hot pink writing make a great koozie/ ink combo. I have been working in this industry for year snow and would have to say it is one of my favorite color/ink options.
Another interesting yet not surprising color combo that is one chosen by many feed and seed stores. This combo is a John Deere Green Koozie with yellow ink. I am assuming the reason they feed and seed stores chose this combo is show appreciation for the greatest tractors known to men.
My personal favorite koozie/color combo is a hot pink koozie with black in, just like the one you see at the top of the page in the picture. The Black ink just POPs out at you.