A word limit is not an arbitrary, petty rule that is put in place simply to annoy you; it is necessary to prevent waffle and to test your ability to present complex work succinctly. It's also a useful guide to how much time and effort you need to invest in the assignment.
It may seem strange to focus on the word count at this late stage in the writing process. Many students obsess about the word count at a very early stage in the writing process - often resulting in a reluctance to edit, or causing them to run out of words before everything has been written. The best time to think about your word limit is when you have finished writing, this way you can get all the necessary information down without worrying. If you leave the word count until late in the writing process, you'll can be much more thorough in the editing process and really focus on getting rid of all unnecessary words.
Some students are used to writing to word limits that have a 10% 'margin of error'. It is not safe to assume that this will be the case at university. You may find that a word limit is strictly enforced, so err on the side of caution and ask your tutor.
If you have a tendency to be a little 'wordy', there are things you can do to trim your work. Take a look at these top tips for writing within the word limit:
1. Do a word count. If you are hugely over the word limit, you will need to be very strict in your editing: get rid of any material that's not strictly necessary.
2. Cut the waffle. Look for ways to make your points in fewer words. The ability to write clearly and succinctly is a key part of the academic writing style.
3. If you are only slightly over the limit, scour your work for any redundant expressions. There are some examples of redundant words below (the redundant word is in brackets).