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A mid-length bob flatters almost any face shape. However, it can be difficult to keep this stylish cut smooth and sleek throughout the day -- especially in humid conditions. Fortunately, with a few tips and helpful products, you can keep your beautiful bob curled under from dawn to dusk.

Shower and wash your hair normally.

Apply a pre-styling product to your hair to help it behave. If you have fine, thin hair, go for a light mousse or gel mousse. Those with medium-textured hair can use either a mousse, gel mousse, gel, glaze, liquid serum or cream. If your hair is thick and textured, you'll need a heavier product, such as extra-strength mousse, gel, cream or wax.

Blow-dry your hair with a paddle brush until it is just slightly damp.

Separate your hair into sections and blow-dry each section with a round brush. A round brush will encourage bend and volume and make the straightening process much easier.

Straighten your hair with a flat iron, beginning at the bottom layers closest to your neck. Separate your hair into sections as you did in step 4. Straighten only the ends in order to keep the volume you created at the crown through blow-drying with the round brush. Remember to tuck the straightener under while finishing the ends to create the under-curl.

Spray your hands with extra-hold or anti-humidity hair spray and run them along the top of your hair. Spray your hands again and use your hands to pull down on the ends of your hair, curling them under as you would like them to stay.