Well one option is to recruit a skilled animator! Like anything, to do animation well takes time and practice.
But - if you really want to animate yourself I`d suggest doing some basics first, like the first exercise I did at Uni was to draw about 4secs each of:
1. a bouncing ball
2. a balloon
3. a heavy ball dropping
If you can animate those 3 convincingly then those techniques can be used in various combinations to create all sorts of other animations (not always using balls obviously - rather it shows you can express a sense of weight/timing etc).
Also - the guy who did the original prince of persia rotoscoped home video footage he made which helped a lot rather than drawing all from scratch, but you still benefit from being able to draw basic animation when it comes to cleaning up the converted frames.
see `POP` video examples here -
Another World was rotoscoped too -
http://en.wikipedia.org/wiki/Another_World_%28video_game%29