For the mane I definitely recommend cutting straight up into the hair. It takes patience at times but it gives the best result. It may still not look as natural as you'd like when you first do it, but give it a few days and it will get sorted out and look natural and beautiful again. =)
For the tail, banging it is always good because it makes it look thicker and overall tidier. Layering makes it appear thinner, so I'd only layer a crazy-thick tail to make it easier to brush and maybe look more normal..
For the best result banging a tail, grab the tail at the top making sure to get all of the hair in your hand, slide your hand down as straight as possible, get a tight grip on it at the bottom (leaving a few inches more than the amount that you want to cut), bring it up to where you can see it and cut it, then cut it as straight as possible. Sometimes it helps to use clippers but usually I'm too lazy to bring them out for that and scissors work out fine for me so far.
Last edited by rocky pony; 01-03-2010 at 04:47 AM.