Although it's hard to really screw up a salad, it's just as tricky to make it unforgettable.
Here are a few tips to make your green salad a show-stopper:
After you (gently) wash your greens (try not to crack the leaves), soak them in cold water for a few minutes. This will let them soak up some lost water, and make them crunchier than they would otherwise be. Give them a (gentle) stir with your hands, so any last remnants of grit will sink to the bottom
After soaking, lift the greens out of the bowl of water so you don’t re-pour grit on them.
Dry your leaves thoroughly (a salad spinner is great for this-- though don't overpack it), or the dressing won’t coat the leaves (that whole oil-and-water thing).
Tear big leafy greens (like red leaf) along their rib so they retain more of their original shape. Tear them small enough to fit onto a fork/in your mouth, but not too small, or else it will look like a Caesar from a pizza place. Leaves like endive and romaine hearts look more elegant whole, so just serve a knife with those types of salads.
Delicate herbs (basil, parsley, mint, chervil…) are a lovely addition to the greens (save woody-stems—thyme, oregano, marjoram— to chop up the dressing).
There should be at least one crunchy, non-fresh-vegetable element: croutons, nuts, bacon, roasted chickpeas; and one creamy/rich element, like cheese or avocado.
Fruit, like pomegranates, thinly-sliced kumquats, blood oranges or roasted pineapple adds bursts of juicy tartness and bright, beautiful colors (in the springtime, local strawberries and cherries are great additions).
Croutons are best torn, not sliced: tear rough pieces of a good country loaf, toss in olive oil, and season with KOSHER salt. Bake until the edges and outside are quite brown and crispy, but interior is still a bit soft. This gives you a variety of textures, and can soak up some of the flavors of the salad.
Dressing should be simple. Thick, creamy dressing should be a dip for cut up veggies, not used to drown delicate leaves. Lemon juice and olive oil are usually sufficient—but perhaps mince a little shallot and some herbs in there too. The classic vinaigrette ratio is 3 parts oil to 1 part acid
Dress your salad RIGHT BEFORE you serve it. And season it with KOSHER salt, and some FRESHLY-GROUND pepper.