Now that I made my first flash, I can go over somethings that are quite useful to know.
1. If your using voices or music, get them early.
This is important for a few reasons.
A. It gives you an idea of the size of the flash
B. It gives you an idea of the length of the flash
Not to mention the lipsinking needed for your characters
2. Just accept what you can do.
Now you may get to a point where you got the right kind of drawing for a scene, but the problem is that it's the last frame of the scene. What you could do is re-draw; where you basically can redraw from the first part so that it would look like the last frame.
This is a taxing techinque however. It's quite possible to not be satisfied with the drawing and continue to redraw the scene over and over again. It's at that point where you just have to accept it, and move on.
3. Pratice, pratice, and pratice
Don't worry, you'll get better, no one is born like this. If you think your taking to long, just remeber K.I.S.S. (Keep It Simple Stupid).
I'll have some more up in a bit, but for now I got to go back to my flash.