I often see tatoos that don't seem to make any sense or ones that say Love in chinese and kill in english or what not. Then there's the mixing of Long form and short form characters.
Chinese is not an alphabetic language. You can't really spell things out from english. There are transliterations, and they are becomming more and more common as new ideas and products spring from the west. BUT. Chinese is pictographic. The obviousness of the pictures has faded with simplification over the years but is still based on pictures. You can't spell in chinese. No ALPHABET! (try japanese or korean, thai , tagalog, tho they don't look at all chinese)
THere is no spelling... each character is a word (with rare exception) and sometimes a character or 2 characters can represent a phrase or idiom.
When people transliterate their names, it often doesn't sound anything like the original and is really a re naming. Some names.. such as biblical ones haev common translations. But odd ones (becca) do not. I have chinese speakers refer to my surname as Luo3 (pinyin) (nothing like my last name, i have an R .. nuff said)as it is one of the Laobaixing (common last names), makes more sence to PRC/Taiwanese chinese. ABC and americanized chinese are of course more flexible.
If you try to write a nick name or transliterate a name or write a western idea on your person, you may not be happy, long term. If I were to try to transliterate my full name with my education, experience and tools at my disposal (native speakers) I would still have a misunderstood tatoo. Laymen and chinese alike would tell me it meant somethnig funny. I'd have to explain it all the time.
My OPINION is that chinese tatoos are best left to the Chinese.
Have you ever read the instructions from a really cheap foreign made product.. Probably got a laugh out of them didn't ya.
"happy fun lighter, to make fire ignite, inject digit on fire maker handle, indicate up down vibration with body, use fire burn cigar stick. Enjoy, reuse."
(and you want to tatoo that on you?)
But if you must get one. Try getting a dictionary (for a single chinese wor, cross referenced) , or a chinese friend. i mean Chinese chinese, SOME 2nd generation and beyond folk are a little more proud than they are knowledgable.
Often times things are not translated word for word in any language. So finding a character on a lantern for instance, having the store keeper say it means welcome or something, might be the GENERAL meaning. A loose translation. Western ideas (angel) are not likely to work well either. A bird or something would likely be fine, dragon if you must. But to be remembering

little story...
Once in one of my classes, we all had chinese name tags, someone decided to change their name because they didn;t like the character. They X'd out the old character and wrote the new. When our Teacher came in he became very agitated and wanted to know who did that to him. Before class would start he destroied the name tag and wrote a new one in caligraphy. He didn't say why it was such a big deal (maybe just to him) but i don't cross out peoples names like that just in case.
But to reitterate == Names.. no go... nicknames.. no go... phrases.. I love so and so... like someone said Wo AI then english.. no go.
What's the big deal any way. Most of the folks i see flouting them are White. Be proud.. (*contrary to popular belief, white people can be proud, just don't get all jingoistic) get an ancient english tatoo (there are fewer english scolars than chinese to read it) Or german or sweedish or whatever. Be anglo, Italian , polish, russian, whatever (*tho russian tatoos are potential maffia signs, be careful, not my forte). Nothing like a big celtic cross or knot. And anyway.. they're quite passe.. everyone has one (i guess no more than the knot). They have temporary kits with all the luck love wealth and longevity you want.
my long winded opinion. (that i share with strangers with funky chinese tatoos)