Use the handle of a rat-tail comb to separate a thin strand of hair from the middle section. Pull it taut so that it is perpendicular to your head. Select a strand that is no larger than the diameter of the perm rod you plan to use, since packing too much hair onto a rod can result in limp curls. You can start at your front hairline or at the back of your crown. If you did the latter, you’ll have to go back and do the front once you reach your nape. Place an end paper against the hair strand, so that half of it is hanging off the side. Fold the excess paper under the hair strand so that it's sandwiched inside. Next, slide the end paper towards the bottom of the hair section. It would be a good idea to fold some end papers in half ahead of time. This way, you can just slide it over the edge of the hair strand, then pull it down. Place the end of the hair strand on top of a curling rod. Wrap the hair around the curling rod until you reach your scalp, then close the rod.  Choose a rod size that’s appropriate for the curl size you want. Remember: the larger the rod, the larger and looser the curl. Roll the rod downward, away from your forehead and towards your nape. If you started from the back of your crown, work your way down to your nape first, then go back and do the front section. If you started from your hairline, just work your way down to your nape. Make sure that all of the hair from the middle section goes into the rod. Choose a side to start with, and unravel the run. Create a vertical part, somewhere behind your ear, and wrap the front section of hair into a bun. Apply more rods horizontally in a vertical column, then do the front section of hair (the one that’s in front of your ears).  The ends of the rods need to be touching each other--including the side-back section and the middle section. Start applying the rods at the top of the side section, right under the middle section, and finish at your hairline. At this point, your hair may start to dry as you work with it. If that happens, simply mist it...

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Write a summary of the previous text in Vietnamese:
Lấy một phần tóc mỏng ở phần giữa đầu. Gập giấy quấn đuôi tóc vào đuôi của phần tóc. Quấn tóc xung quanh lô cuốn tóc. Lặp lại quá trình trên cho toàn bộ phần tóc ở giữa. Quấn 2 hàng lô cuốn tóc cho mỗi bên. Quấn băng bông vải xung quanh đường chân tóc và nhét bên dưới các lô cuốn tóc.