Consider your skin tone. Most colors show up well on very light to medium-tan skin, while those with darker skin tones have fewer options. Black, dark blues, greens, reds and purples show up well on darker skin, while yellow and orange have a tendency to disappear.
Think about colors in terms of the tattoo you want to get. A purple butterfly may convey calm and wisdom, while a bright orange one may tell others that you are energetic and extroverted. Similarly, combinations like black and red or blue and purple may evince feelings of depression or sadness. Think carefully about what you want to tell others with your tattoos.
Keep in mind that colors fade faster than neutrals. A colorful tattoo needs more touch-ups than a black one. If you're short on money or want to avoid as much pain as possible, choose a black design. Many darker designs have shading that make them as dynamic as colorful ones.
Test the colors before you get your tattoo done. Some colors may cause allergic reactions; ask your tattoo artist for test dots on a hidden part of your body to make sure that color won't affect you in larger amounts.