Whats the best way to practice double jumping on kha'zix

So I've shifted to being a k6 main. Not because he's broken, but I was kind of looking at him to begin with. The basics of k6 aren't too hard to learn. It's just like yi and Eve where everything is heavily decision based. But then with yi, yasuo, etc, you have the yasuo who are good with the wind walls, yi's who dodge towershots and skillshots with q. For k6, it's the double jump. I haven't practiced it yet but would like to get good at it so what's the best way to practice.