I recommend the refrigerator test. If you find something you like and might want inked, get a copy of it and hang it on the fridge or someplace you will see it multiple times per day. If after minimum 3-4 months (the original recommendation was 6) you still really like it and want it done, then go for it. I have never followed that one myself, but aside from my first one (typical tribal band with yin yang, working on getting rid of it) which I got in Oz, I don't regret any of them. I kind of wish I had come up with an orignal dragon drawing instead of the one I got, but I still like it.
And if you are going to get kanji, make sure you know what it means FOR SURE. I have kanji on my back, a remnant from my MMA days, and I have the framed piece of paper with the original script on it in old style kanji, which was supposedly done by some old dude in Japan (I got it done in Guam). It says, 'Live as a man, Die as a man, Be a man', and I have had random Japanese people read it to me (always funny, as if they think I don't know what it really says).
Best tip: come up with art that means something to you, and have it drawn up by a good tattoo artist. That is the deal with my latest, St Michael killing Lucifer (yeah, I know I'm not the first to get that, but mine is drawn a little different from the typical scene). I have my kids handprints on my chet over my heart, and I have plans for two more down the road. Both will be related to what I do, but only one of them will be 'sort of' blatantly military.