The right shape can make you look thinner, younger -- even happier. Rach's buddy Gretta Monahan tackles common brow blunders (as modeled by our courageous staffers). Identify yours and get grooming.

eyebrow shapes

 Not sure where your brows should start and end? Rach's buddy Gretta has a trick. Just find a chopstick or pencil and get started.

1. Place the chopstick vertically along the nose until it meets the eyebrow. Tweeze anything that falls before this line.

2. To find the arch, slant the chopstick upward from the outer edge of your iris.

3. Slant the chopstick just beyond the outer corner of the eye.

 See how Gretta tackles these common brow blunders.

 The Plan
 Trim and shape hairs while lengthening the brow. Use a brow pencil to fortify and extend brows at ends.

The Tools
 Eyebrow pencil, eyebrow brush, mini scissors and slanted tweezer

How to Groom
 1. Brush all hairs upward with an eyebrow grooming brush or dry toothbrush, then use tiny scissors to trim any tips that stick out.
 2. Using a slanted tweezer, pluck strays from beneath your brow to help elongate and slim the face. Grab hairs at the base to avoid painful tugging. Follow the natural curve of your eyebrow.
 3. Sharpen the shape: Your eyebrow should arch at a spot above the outer edge of your iris. Carefully remove only the stray hairs below the peak -- never dig into its middle.

 The Plan
 Fill in overplucked areas. Focus on the uppermost part of brows to create a natural eye-lift effect.

The Tools
 Eyebrow stencil, eyebrow pencil and mini scissors

How to Groom
 1. Use an eyebrow stencil -- the Anastasia Brow Express kit ($38, anastasia .net) comes with four options -- to shape an arch with a brow pencil or powder, applying color in small, upward strokes. Press lightly to avoid a drawn-on look, and keep stepping back from the mirror to check your work.
 2. Superskinny brows may still have areas to trim. Cut the spiky innermost part of the brow (closest to the nose) to make an even line. Keep up with this technique while growing brows out, too.

 The Plan Deepen sparse or light-colored brows to frame the face.

The Tools
 Angled brush, eyebrow powder and eyebrow gel

How to Groom
 1. For a natural look that doesn't seem drawn on, dip an angled brush -- it helps with precision -- in a powder shade that closely matches your hair color (for superlight hair, you can go one shade darker). Apply it over the existing hairs to better define brows, then continue to fill in any gaps in the shape.
 2. Highlight your work with a clear brow gel or cream.