Some of this is going to be boring. If you came here looking for the magic formula which will give you success then you are out of luck. But there are some tips which are worth taking on board.
Work At the Subject
It sounds riduculous, and I'm sorry about this, but we have found a definite link between the students that do well in the subject and those that work at it. It is best if you treat the work as a "day job" in that you set yourself out to do the work 9 to 5. The whole point of student life is that you enjoy the subject that you have signed up to do, so not all of this should be totally unpleasant. Do things like read around your subject, hassle the lecturers if things don't make sense and above all, start your assignments as soon as they are distributed, not the day before they are due in. And prepare for exams.
Broaden Yourself
By this I don't mean lie down in front of a steamroller. What I mean is do things other than write computer programs. To really do well in this (or indeed any) business you have to be able to get on with other people, some of whom will not actually be that interested in computers (scary but true). To this end you might find it useful to join a club or two, form a band, write for the student newspaper, do some drama even, anything like that. When you go for an interview for a job it is very nice to be able to talk about the wide range of interests that you have over and above things on the end of keyboards.
Put Yourself About
It doesn't matter how good you are, if nobody has heard of you then you might as well not exist. You should attack this issue by getting invovled in student events, competitions and even start blogging about yourself. If your department has a forum, get involved in that. Ours is very active, and has all kinds of discussions going on at any time. Lots of second and third year students at Hul get involved in the first year subject forums, dispensing advice and comfort because they have been in that situation.
Manage "The Brand that is You"
Putting yourself about is a good thing. But don't go mad. Remember that drunken pictures you put up on your Facebook site will be out there for ever. Send something onto the internet you can never get it back. Even things sent to "friends" have a way of surfacing years later, sometimes in the most embarrasing ways.
Potential employers will definitely search for your name as part of the recuitment process. If they find a whole bunch of stupid photographs and posts about "How much you hate your boss" then this is unlikely to play well when you are job hunting. Make sure that when someone searches for your name they find good stuff, well written blog posts, interesting articles and helpful forum replies. This is not to say that you need to create an artificial persona, more that you have to make sure that the "tip of your iceberg" that shows up on the web is the best looking part. And never, ever put anything out there that shows you in a bad light. If you think this is almost an exercise in "Brand Management" then you are pretty much right.