So I finally started doing sentences and decided to begin with Toki wo Kakeru Shoujo (thanks cb4960!) and put the words I don't know (most of them actually) on a separate deck, but now I have a question.

When I add a word to that vocabulary deck, how do I know if I should write it in Kanji or not? For instance, should I put "嫌" or "いや"? How do I know which is more common? Or, even if いや is more common, how do I know if 嫌 is worth srs-ing anyway "just in case"?

I thought I'd look at WWWJDIC's example sentences and see for myself which is more common but I'm not sure. For example there are 6 sentences with 嫌 and 4 with いや so I thought I'd learn it as 嫌, but what if there was instead 8 いやs and 2 嫌s? Is there a better way to tell which is more common and when?

Thanks in advance.

I don't use just plain vocab cards personally, but if its bothering you why not just include two cards? One for いや and one for いや. They're vocabulary cards, so they should be very quick to go through and answer; it shouldn't take too much extra time to do.

EDIT: Actually scrap that. I tend to find that if I can read the kanji, I will also recognise the kana version of that word when I see it. So just use the kanji version of the word. Don't worry about which one is used more often because that's not something that can really be transmitted by just a vocab deck. That information only comes from reading sentences, and seeing which ones use which forms of the word. Since you're losing that information anyway, you may as well just go for the Kanji word.

Yes, that's what I was doing before and I guess I'll keep doing it. Thank you.