-always apply for jobs above yoru current ability level. I have never been able to do a job i have applied for - you need to get out your comfort zone. So I would apply for more senior roles and convince them i could do it at interview. Makes for a stressful life but is the best way to progress.
-be ruthless and don't have too much loyalty to a company. I change jobs every 2 years. I ask for a payrise dependent on my performance - if I don't get it I leave. That is the best way to hike your salary up.
-Always say yes (at the beginning anyway). If someone says 'can you do that' say yes, even if you can't. When you have worked your way up to a level of seniority that is when you can start saying no - when you are a junior you have to do everything to get yourself known.
-you need not be the cleverest of most experienced person (I certainly am not) but make sure you are always competent and calm and willing.
-If you are a woman in a male dominated environment (like me) be emotionless.
-Get as many qualifications as you can even if it nearly knackers you in the process. I would never be where I am now without the 2 degrees I studied for whilst working part time.
-Work hard. I am always available to work. I generally am at the office 8-6 Mon to Fri and that is pretty slack compared to others. However I have 3 teleconferences with Far Eastern contacts a week, and these take place from midnight - 2am. I also work every Sunday afternoon to catch up on what I have not managed to complete in the week. I also am on the phone a lot in the evenings due to time differences (my manager is based in California). I spend about 12 hours a week on teleconferencing (mumsnetting at the same time) which is an absurd waste of time really, but you have to make your presence felt.
-you HAVE to enjoy it. I love my job. The hours are getting me down but I am at a level of seniority where I can delegate the crap work, and concentrate on the good stuff.