How to begin translation ?

Hello.

I am trying to traslate webissues to japanese lang.
but I don't know how to local build for testing my translation.

I tried following
1. download webissues source code.
2. japanese translation created from client/translation/webissues_untranslated.ts .
3. use linguist and release
4. ./configure && build

but I can not confirm japanese strings .

anybody please help me .

thanks.