In one sentence, describe what the following article is about:

If you ask someone for a favor at an inconvenient time, you can embarrass or even anger him or her. You also might decrease the chances he or she will say yes. If you're going to ask your teacher for help with your math homework, don't ask in the middle of his lecture.  Definitely  don't ask right after he's learned his house has burned down! In general, try not to interrupt someone's work nor their moments of joy or sadness. Depending on the favor, you might also want to move to a private location when you ask your person. If your favor's embarrassing to you or this other person (for instance, if you need help removing a wedgie), don't ask him or her in front of other people. The sooner you mention your intentions, the better. It's polite to be up-front about you want, but it's also a smart use of your time. If you ask for a favor at the end of a long conversation and your helper says s/he can't help you, you've wasted time you could have spent looking for another helper. It's simple - all you need to say is something like, "Hey, I was wondering if I could ask you a favor" within your first few sentences. Then, simply launch into your request! Your potential helper will probably appreciate that you weren't sneaky about what you wanted! You want to be polite and gracious while also being crystal clear about what you want. Explain the facts of the situation. Leave nothing to guessing. Then, without dallying, explain what you need this person's help with. Ask them plainly if they'll help you in the form of a simply-worded question. Don't allow any chance of misunderstanding. If this issue is important enough to require a favor, you should address it head-on. Say "Do you think you can help me with my math homework for an hour tomorrow?", not "Hey, if you want to show me some math stuff, that's cool!"  Specify any relevant deadlines or qualifying information up front. For instance, in our math homework example, if you've got a test at the end of the week, be sure to include this information so the person will know s/he will have to free up time before then. Don't try to coerce or guilt someone into doing you a favor. A favor isn't a favor unless it's given genuinely and willingly. Don't procrastinate - the longer you wait before bringing up your need for a favor, the bigger chance you have of losing your nerve and leaving the conversation without even having asked. If you let this happen, you'll be back to square one! Make your greeting, exchange one or two short pleasantries, move to a quiet area if you need to, then immediately tell this person that you're looking for a favor. Don't let him or her get away before you gather the courage to ask! Let this person know that they're the only person who's good enough for the job - even if they're not. Compliment this person's abilities - in our example, we might say something like, "Could you please help me with my math homework? You're crazy good at trigonometry - didn't you get an A on the last test?" Your praise can range from subtle to gushing, depending on how desperate you are for help! People who are reluctant to help you can be swayed if you tell them the consequences (for you) if they don't  grant your favor. Tell them the  worst-case  scenario of what will happen if they won't help you out. In our example, you might tell your potential tutor that if you can't get help with your math homework, you'll definitely fail math! You don't have to be over-the-top or maudlin to get your point across, but if you're desperate, it can help! " If you're desperate for a favor, it can be quite tempting to shoot down a potential helper's excuses for not being able to help. If you do this, though, you'll regret it as soon as the favor's done. For peace of mind and to avoid lingering awkwardness or hurt feelings, it's a good idea to include a subtle "exit strategy" for your helper when you ask for a favor. Mention a potential reason why your helper might not be able to grant your favor - they'll probably take this excuse if they don't want to help. In our homework example, we would say something like, "Hey, I'd really appreciate it if you can give me a hand with my homework,  unless you're busy or something. " The act of asking for a favor implies that there's a possibility they'll say no. Prepare for this possibility! Don't get upset if this person can't help you - instead, be happy that s/he was honest about his or her capacity to help you. If, out of guilt, they had offered to help you, only to withdraw their help later, they would have cost you valuable time. By being up front, they've given you a better chance to find help elsewhere. Tell them that you understand and don't ask them for a favor again.  You can, however, ask them if they know anyone else that can help. With luck, they'll be able to recommend someone you hadn't considered. Don't take it personally if someone can't do you a favor - it's not a reflection of their opinion of you. If you suddenly start ignoring this person, s/he will think you only cared about his or her ability to help you. Asking someone a for favor doesn't necessarily mean they'll agree to help you! They may be too busy to help or may not know how. They may simply not want to. In any case, don't be too emotionally invested in your first choice - have a few alternate options in mind in case you need to look for help elsewhere. In our math homework example, for instance, we would first plan to ask the girl in class who gets straight A's for help. If she can't help, we'd then ask the boy who answers the most questions in class. If he can't help, then and only then will we approach our standoffish teacher.

Summary:
Approach your helper at an appropriate time. Tell them you're looking for a favor. Word your request for a favor carefully. Get to the point. Flatter your helper. Offer this person a reason to help. Give your helper an "out. Accept refusals politely. Have a backup plan.