First off, thank you for considering contributing to LyttleScoreboardEconomy. It's people like you that make LyttleScoreboardEconomy such a great tool.
If you've noticed a bug or have a feature request, make sure to check our issues if someone else in the community has already made a ticket. If not, go ahead and make one!
If this is something you think you can fix, then fork LyttleScoreboardEconomy and create a branch with a descriptive name.
A good branch name would be (where issue #325 is the ticket you're working on):
git checkout -b 325-add-japanese-localisation