How to Curl Your Hair Overnight
To curl your hair overnight, start by dividing your hair into at least 4 sections. Next, twist each section into a little bun and secure it in place with an elastic band or hair clip. Alternatively, cross 2 bobby pins at the base of each bun so they form an “X.” Then, leave the buns in place while you sleep. In the morning, remove the elastics or clips and run your fingers through your hair to form loose curls.
Split your hair into sections. You can actually use as many braids as you want. The fewer braids you use, the larger the curls will be. So decide how many braids to use based on how large you want your curls to be. Braid the sections of your hair. To braid hair, you just divide the part you want to braid into three sections and bring the far left piece across the middle section, then repeat with the left piece. You continue doing this (alternating between the left and right pieces) until you have no more hair left. Tie off the end with an elastic band. Go to sleep. When you wake up, take the elastics out of all the braids. Run your finger through your hair to create the curls. Set your style with some hair spray. Split your hair in two parts. It is usually best to split the hair down the middle, but if you have a natural part in your hair that is close to the middle, that can work too. Create a french braid on one side. To do this, you simply start by taking a section of hair from the top of your head. Split this section into three parts and start braiding like normal, except that you keep adding hair to each side as you braid. Keep going until there is no remaining hair to braid. Tie off the French braid with an elastic band. This style will result in straighter hair on the top half and curly hair on the bottom half. Repeat the previous step on the other side. This will result in two French braids in your hair, one on each side of your head. Go to sleep. When you wake up, undo the braids. Run your fingers through your hair. The bottom should only be curled. Set the style by spritzing it with hair spray. Divide your damp hair in two parts. The sections should be even and split in a place that makes sense for your hairstyle. Keep the part of your hair in mind when choosing where to divide the hair. If your part is in the middle, consider dividing your hair down the middle. If your part is off to one side, it might be a good idea to divide your hair using the side part. Twist and clip one side. Take one section of your hair and twist it repeatedly until it is in a tight twist (though do not keep twisting once the section starts to twist on itself and create a bun). Take the twisted length of hair and clip it on top of your head using a crab-clip. Do the same thing on the other side. Make sure both sides are clipped properly and comfortably. Remember, you'll have to sleep with this style in. Go to bed with the style. When you wake up, take out the clips and run your fingers through your hair. Set the waves by spraying them with the hair spray. Take a section of hair and twist it. This step will be similar to what you did for Method 3. Take one section of your hair and twist it repeatedly with your hand until it is wound as tightly as it will go into a little bun. Note: If you want tighter, smaller curls, you can divide your hair into more sections. The more sections you have, the smaller your curls will be. Secure the bun in place. For this step, you can use any kind of elastic band or hair clip. Note: Remember that you'll be sleeping with the clips in your hair. So try to clip them in locations on your head that will still allow you to sleep comfortably. If the clips are too painful to lay on, you can use elastic bands to secure the twists or use two bobby pins in an X formation at the base of each twist. Repeat the previous step. Twist mini buns all over your head, making sure to use all of your hair. Go to bed with the style. When you wake up, take the buns out. Run your fingers through your hair. This makes your hair very curly. It may come out as frizzy, so make sure to put a serum in the night before. Try doing an updo or a high ponytail with this style. 
Split your hair into sections. Braid the sections of your hair. Go to sleep. Run your finger through your hair to create the curls. Split your hair in two parts. Create a french braid on one side. Repeat the previous step on the other side. Go to sleep. Run your fingers through your hair. Divide your damp hair in two parts. Twist and clip one side. Do the same thing on the other side. Go to bed with the style. Take a section of hair and twist it. Secure the bun in place. Repeat the previous step. Go to bed with the style. Run your fingers through your hair. 