1. Break it up a little bit.
When I say you can rock a monochromatic look, I mean that it's relatively easy to pull off similar colors. A nude colored dress with nude colored shoes, though, can look a little... nude. Create a little bit of visual contrast either by mixing up your tones on the top and bottom, adding a subtle print or some texture, or adding in some accessories, like shoes or a belt, that offer a little contrast.
In my case, I went with a bold, red lip, but you could do brighter blush, a smoky or tight-lined eye, or anything else that gives your face a little brightness, color, and contrast.
2a. And make sure your skin looks perfect.
Seriously, don't skimp on the concealer. That zit is way more noticeable when it's the only spot of color for several feet.
Um, maybe not the best example picture because my mole kind of looks like a zit here.
3. If you're taking photos, do it against a darker background.
4. Don't listen to any of these rules because rules are for losers.
Not actually true, but particularly if you're not trying to take pictures, you can disregard most of this and just go for an ethereal, sparkle fairy princess thing. Although you should still probably follow 2a.
What are your fashion rules, and what rules do you like to break?
Blouse: 80s does 40s sheer pink blouse, LexisMonkey via Etsy
Skirt: High waist interlock skirt, American Apparel
Hat: 40s (?) beaded velvet headpiece, Vintage Underground