Hmm. I just tilt and rock the carboy back and forth really hard for about 5 minutes. No lifting. Seems to work for me, although I have bought a mix stir recently which is easier, but not helping me built up my biceps ;-)
The thought of tilt and rock scares me to death these days, even though that's what I used to do. It just seems like one of those things that will work great right up til the day the carboy breaks.
Simple, low tech solution - place carboy in plastic milk crate. tip crate up on edge (one hand holding top of milk crate, the other on the top of carboy). Rock back & forth. This protects very well against potential breakage while also making the mechanical action of rocking back & forth very easy. You can aerate your wort very effectively.
I have a plastic milk crate for each of my glass carboys. Use them for storing, moving, etc. Also protects against one carboy knocking up against another - with potentially disastrous results. Keeping the carboy in that protective container is a good precaution throughout the cycle of carboy use. Be safe.