Most people are prone to procrastination when faced with a task they do not enjoy. To help overcome this, try to identify what causes you to procrastinate and take steps to avoid it.

If you do not know where to start, break the task down into smaller chunks and pick them off individually If you are paralysed because you want perfection, write freely but give yourself time to edit and polish at the end
If you delay because you know it is going to be difficult, plan a reward for when the work is finished.
There are many other techniques available to help you address procrastination. Find out what works for you and eliminate the stress caused by last-minute working.