Hand launching an AXN Floater Jet, a Bixler, or any high-mount pusher can be a little tricky because increasing the throttle, especially at slow speeds, can cause the nose to dip. You get this little surprise usually about a second after releasing it. All great advice on this thread... aim a little high, 50%+ throttle, and the only tip I would add would be to quickly get your thumb back on the elevator and pull back an instant before increasing the throttle. Kinda like a gas pedal and clutch relationship on a car. Add a little throttle and ease back on the elevator... in unison. It's so easy, you'll very quickly get the hang of it, probably the first attempt. My floater jet is pretty nose heavy anyways and hand launching by myself is still easy doing it this way.
(Great... now I've jinxed myself. Do I have a nose-dive launch in my future??)