The square nail is the classic acrylic shape — straight side walls, two sharp points on the tips, and a balanced C-curve. It is the staple shape for the traditional French manicure and is used frequently for detailed nail art designs.
But the square nail is not always the best choice for certain nail beds. According to EZ Flow educator MaeLing Parrish, the square shape is difficult to pull off when the natural nail bed tends to be shorter and wider. In such a case, a sharp square nail could make the nail appear shorter and stubbier. But for longer nail beds, the square can complement the nail and add length to the finger.
How to File:
To file into the classic square shape, Parrish instructs that a medium-grade file (150 grit) should be used to shape the free edge and side walls first. Then turn the client’s hand around to straighten the free edge, noting that when looking at it the file should be perpendicular to the nail to achieve the hard square. File the side wall straight up and then change the angle to blend. Repeat this on the other side. Once both sides are finished, use angles to lightly feather and bevel the nail and to sharpen the corners.