What is a one-sentence summary of the following article?
Avoid wavering and appearing indecisive, which can confuse the other person. If you're firm when you turn them down the first time, you probably won't have to have the conversation twice. An ambiguous reaction from you could make the person feel like they still have a chance, which wastes their time and isn't fair to them. It also increases the likelihood that you'll need to repeat this awkward conversation with them in the future. Approach them with a smile and keep your demeanor as calm and relaxed as possible. Use positive body language, such as sitting or standing up straight and looking the other person directly in the eye, to convey that you are serious. Negative body language, like slumping or not looking them in the eye, indicates a lack of confidence in your own words. If you truly aren't interested in dating this person, make that fact clear. Statements like "I'm too busy with work right now" or "I just got out of a long term relationship" may seem like kind responses, but to the other person this could sound more like, "Ask me again in a few weeks." Avoid making it sound like there is a possibility for a future date, especially if you know there isn't. Don't continue to stay in contact with a person that you have zero plans to ever actually date. Sometimes it can feel good being around someone who you know really likes you, but unless you are serious about returning the sentiment, you are simply feeding your own ego by doing it. Don't re-initiate communication unless you're really interested. It can be tempting to reach out to someone who you've turned down in the past, especially if you are going through a rough patch yourself. Unless you are truly interested in the person, there is no need to call, text, or even be Facebook friends with them. The infamous drunk dial (or text) is a common way people end up re-initiating contact. A momentary lapse of judgement on your end can cause a lot of confusion and despair for someone else. You'll also be putting yourself in the position to have to reject them again. Do you really want to be friends, or are you just trying to spare the other person's feelings by saying so? If it's the latter, just don't say it. If you truly do want to remain friends, give the person some space after you reject them. Give them a chance to get past their bruised ego and embarrassment. It's possible that the other person may not feel capable of being friends because of their romantic feelings for you. If that's the case, you will have to respect that.

Summary:
Be firm and absolute. Speak kindly and directly. Don't offer false hope. Move on. Avoid the friend-zone unless you actually mean it.