Easiest way to learn Japanese?
Go to a Japanese school. It's so hard to learn all the characters without schooling. But if you're talking about just speaking Japanese, Rosetta Stone or something would be good.
Practice, confidence, and having a good attitude about it! (your grumpy cat profile picture isn't a good start ;)
Live in Japan from what I understand its a difficult language to learn
Live with a Japanese family that speaks no English. Total immersion! But take a dictionary!