I recommend using a Mirror for this. Right think of the important phonemes such as "ee" "pp" "th" "o" etc and see what position your mouths positions itself into and draw what you see in the style of your cartoon.
Now you should have each phoneme on a seperate layers, create a new layer but make it a switch layer this time (which is like a folder) and put all of your phoneme layers into the switch layer folder.
Switch layers will only show one layer at a time, which is handy for this tyoe of animation as we don't want the 'ee' mouth showing while we have the 'th' mouth on. To switch between the layers, right click your switch layer and click on layer from the menu that you want to show.
So to apply this to your tie line, go from say from '1' and put in a close mouth layer there, then go to frame '15' and put in an 'oo' mouth, then frame '24' put in open mouth, then frame '26' put in the closed mouth again.
You should notice a sharp movement between the the mouths. This is a very basic form of lip sync. If you've got the hang of this go and read
this post about 'interpolating layers' for a slicker transaction between the layers within a switch layer.
Hope this helps. Any questions, just shoot.
