This usually involves closing your eyes and scrunching your face up a little – simply imagine yourself through the motions through remembering what your face feels like when you do actually cry. If you’re not sure what it looks like, look in the mirror and pretend you’re crying, then pay attention to how the muscles in your face feel.  Turn the corners of your lips down a little. Try to force the inner corners of your eyebrows upwards. Wrinkle up your chin like people do right before they start bawling. This may look fake if you overdo it, so try to be subtle. The breathing is part of what convinces people that you're upset. Start sobbing by making crying noises and take deep breaths as you do so. Breathe in constantly as if you are hyperventilating. Occasionally add a small hitch in your breathing to sound more authentic. If nobody can see you, run on the spot for several minutes to cause yourself to be out of breath. This will also help to create the blotchy complexion often associated with crying. Once you have the eyes tearing, the crying face and the hyper breathing going, you can add a few finishing touches, like covering your face with your hands, resting your head on a table, or hanging your head to seem like you’re sad.  You could also bite your lip as if you're trying hard to stop the tears. Look away, trying to pretend you're not crying to pull off a double bluff! When you're crying, your vocal cords tighten. This leads to the thick or whiny sounds you make when you try to talk while you're crying. Aim to stutter your words and add in long intakes of breath to add to the effect. This is basically "mind over matter" and the more you act it out, the more your body will acquiesce to produce the effect you're after. If you want to be able to cry on command, you need to relax, breathe, and focus on the reason you’re supposed to be crying. By tuning out any distractions, you will be able to dig deeper into the emotions that you’re portraying. It can sometimes be hard to tell if someone is laughing or...

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Write a summary of the previous text in Vietnamese:
Tạo vẻ mặt như đang khóc thật. Tập trung vào hơi thở. Cúi đầu hoặc che mặt để trông có vẻ thật hơn. Thêm vào tiếng rên rỉ để nghe như đang khóc. Gạt bỏ những gì xảy ra xung quanh. Giấu mặt trong lòng bàn tay và cười nếu bạn không cảm thấy buồn.