Not really sure what it is you do for a living, but there are a few essentials that just about anyone who wants to be successful at any job should do.
A google search yielded me this link:
http://www.30daysofgettingresults.com/
Seems legit, I skimmed over most of it and it looks pretty applicable. The two I agree with most are definitely:
1. power hours
2. prioritizing your day
C. Monday vision
I cannot overstate the importance of peak periods (or power hours as this guy calls it). When you plan for them and execute them, your workload disappears at breakneck speed. I have to second that there are hours where I get more done in one hour than I do in eight. As you learn to enter this state and plan to get there more often, your workload will practically evaporate.
I churn through data, reports. hands-on work, really anything at an abominable rate. I do in not even a quarter of the time what other people in my position do, and I do it BETTER than they do.
Read the link if you're having trouble with carelessness at work. A lot of the stuff on there seems to deal with focussing on the important things and getting the stuff that matters done.
I could give a hundred specific methods for improving results and reaching targets, but that link is comprehensive enough for people beginning to take on more responsibility at work.