[LearnAmazingJapanese]

Well, the tried and true method is the one that Japanese kids use.

Write, write, write.

I would add that as you write, you should say the sound out loud:

Write カ, say "ka" and then repeat about 50x or so.

Not fun, perhaps, but I think it's the best way to do it.

I don't encourage flashcards as the primary way to study writing/ reading because flashcards only involve your visual senses (and maybe aural if you say it out loud). Writing and saying the letter/ character out loud involves visual, aural, and kinesthetic (motion) senses.

If you want to go overboard (but help retention even more), get a brush and some ink and write the characters out reeeealy big.

The more senses involved in learning, the quicker the and more permanent the retention.

Sore ja.