1. You must have an unusual pretty face that can stand out from a crowd. Your eyes musn't be as tiny as Big Bang's Daesung, and you must have pale skin, because that's what SM is looking for.
2. 16 is the perfect age to audition, as I have heard from SM trainees (my contacts). I think it is because that way, you won't have to spend a long time training. Like Jessica from SNSD, she auditioned at the age of 11, got chosen, and spent 7 years training. To me, it's better if you audition between the ages of 15-18. 19 would be too old for SM, but there are some setbacks to it. Like Leeteuk and Heechul of Super Junior, they auditioned at the age of 19, spent 3 years training, and debuted at the age of 21.
3. If they think you've got talent, and you look pretty enough, then they will arrange you to fly to Korea. They will pay for your ticket and airplane fees.
4. There are 3 rounds. One is the kind of audition that you perform with other people. If you pass the first round, then the judges will call you back for a second round, and you will perform your stuff again, only try to improve on it, or else they'll see nothing special and eliminate you. Again, if you pass the 2nd round, then they will call you back again and you perform privately in front of the judges. They may also talk with you about some things, but I'm not sure.
5. Yes, they will try to persuade you, but you can always refuse.
6. Yes, SM will give you a small allowance, enough money to shop around and eat outside. The amount is about like $22 US dollars per week.
7. Yes, like Hyoyeon of SNSD (Girl's Generation), she was a backup dancer in one of BoA's music videos, even when she was still a trainee. The thing is, if you're really good at dancing than singing, then the company will assign you some jobs in the entertainment business, but you'll still train, because the company would want your voice to be as good as your dancing.
8. You must have your mother's permission. From what I know, all the SM artists were allowed to become trainees because they had their parents' permission. If you go without your parents' permission, then there is a chance they will possibly sue the company of accepting you as a trainee without their permission, because it's like the company is 'stealing' you away from them, if you know what I mean.
9. If SM thinks you're skinny enough, then they wouldn't make you go on a diet. But if they don't, then they will make you go on a strict water diet, meaning you can only drink water. This is why most of the SM artists are VERY skinny.
10. It depends on how famous you are, but I think yes. Take Han Geng of Super Junior for example. He became a member of Super Junior in 2005, before the whole world knew about him. Yet, his homeland, China, he immediately became famous, and now some Chinese people have gotten in to SM Entertainment. Example: Victoria of f(x) and solo artist Zhang Li Yin
11. It's better if you just audition as your normal self. The judges want to see if you have a clean fresh look without relying on make-up or anything. If they see you have to rely on make-up in order to become pretty, then they will immediately take you off the list for call-backs. SM is known around the entertainment industry as the company with "fresh looks". So, they only want people who are talented and have fresh looks.
12. Yes, if the judges think you're talented and pretty enough, then they will accept you. But bear in mind that it's no use if you're as pretty as an average person. They need to see that you have the kind of looks that can attract many fans, and also you need to have the 'potential' look, meaning that you have to show confidence when you perform live. Who wants to see singers singing as if they think they're going to die? No one, and that's something you have to avoid.
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In audition, you choose your speciality. If you want to sing, you sing, but they include dancing so be prepared. They'll teach you foreign languages like Japanese, Korean (if you don't know it), English, Chinese etc. Trainees go through vocal, dance, acting lessons and even foreign language and composition trainings. Once you get in, you'll only get about 3-5 hours of sleep everyday.
Trainee cycle = wake up > school > training > dinner > more training > reflect on day > sleep > three or four hours later > starts again.
Once you get in,you'll have-minimum is 3 and the maximum is 6-dorm mates. If you're slightly over weight, then SM will make you go on water diets (meaning you can't eat but only drink water). It's better if you have double eyelids and that your skin is pale. When audition, there will always be a rhythm test, where they play music for about 1 minute and you freestyle to that. After trainin