If you want to make sure your tap handle is seen, you have to know where it's going to be living. Will it be primarily in well-lit restaurants, dark bars, moderately lit coffee shops, or somewhere else? The darker the location, the more important it is to have a lighter and brighter colors and simpler artwork. In lighter locations, you don't need to be as concerned with contrast and detail levels since customers won't need to strain to see as much. Setting can also determine the number of sides that you need to have your branding displayed on. If your handle is sitting on a tap that is on the bar or counter in front of the bartender, make sure your messaging is on the front and back. Will consumers be seeing this handle from the side? Consider putting important messaging on the sides of the handle.
You'll also need to consider the other tap handles that are going to be living next to yours. Are you in the Pacific Northwest, where there are numerous wood grain, laser engraved tap handles? Are you in an area with predominantly modern, clean looking handles? How about height? Are there lots of tall handles, short, or mid-size handles? If you want to stand out, you have to be different in some way. If they're short, be tall, if they're dark, be light, if they're rustic, be modern. Do whatever it takes to catch the consumer's eye during that crucial first impression which only lasts a few seconds.
What about the shape of the handle? Do you want the customer to see the shape of the handle, or is the text or image the only thing that matters? If seeing the handle itself doesn't matter, you should probably pick a dark or medium wood or paint color for the handle and then use light colors for the printed logo and text for best contrast. The dark color of the handle will blend in to the generally darker backgrounds and lighting in bars. Oftentimes, the shape of the handle isn't as important if you want the consumer to focus on the artwork or messaging that's on the handle. The key is to find a way to make the message big and bold. Think of your tap handle as a tiny billboard.