If you are seriously trying to write a long article or even start a book you need to have a comfortable place to work in. This will vary depending upon your personality. Some writers enjoy writing in a quiet room at home, others prefer to write outdoors when possible. Yet other writers find they get inspired and can write more when sitting at a local coffee shop or restaurant.
No matter where you choose to write, find a place that works for you. If you have small children or a busy schedule you may prefer to get up earlier and use that time for writing.
By placing yourself in a comfortable setting you will find that your words flow easily. If your body is not in a comfortable place then neither is your mind.