Wear a hat, a hoodie or a scarf. This may be obvious, but some people think that donning a fedora won't hide the entire tattoo. In some situations where you don't want to offend sensitive people but remain true to your tattoos and your individuality, simply wearing a hat can tone them down enough to negate the stigma of your body art and bring the focus back to something else.
Slap on some shades or glasses. Use your own discretion, but if you have some nice-looking glasses, sport them. If you normally wear contacts, forgo them this once and put on your prescription glasses. It might seem silly at first, particularly if you don't often wear glasses, but, especially combined with a hat or hood, this headgear will definitely detract from any facial tattoos and might even give you an air of sophistication.
Try out a few pairs in front of the mirror and if it works for you, go with it.
Apply make-up to cover up the tattoo as best you can. There are lots of different make-up products available that work to conceal tattoos and there are numerous ways that you can find them. Tattoo shops in your area might supply some or point you in the right direction as well as the make-up counter at a nearby mall. There are also numerous sites online that offer high quality tattoo cover-up kits that you can invest in.