*Plan and plan then plan some more. Plans and goals are always important when deciding to switch careers. Never count on things to go "okay" because they won't.
*Money can be the root of bad career changes. Making more money in a new career may be a good thing, but think about and explore what you might have to give up to get it. People used to working rote kinds of jobs eight hours a day may see big money in another profession, but it might mean difficult hours, long hours and weekend work. Also review benefits because they are a large part of compensation.
*Don't say "If Joe can do it, I can do it." People are different from one another and if you have a friend who moved to a career that looks good to you, only evaluate it on what you can do, not what you think you can do based on what you know about him. Even people we know well often fit into certain circumstances that we ourselves may not.
*Starting at the bottom can be even worse if you aren't prepared. If you change, you will have to ford the gap that lies between what you know and what you will need to know to be a success. Ask yourself about your education and experience and be sure it can fit and adapt into any new career.