Photo Credit: Olga Massov
Here's a tip I learned from Peter Berley about a million years ago when I worked on his cookbook, The Modern Vegetarian. When making a dressing, he always adds the salt and other aromatics (i.e. shallot, garlic, ginger, dried herbs, if you happen to be using them) to the acid (lemon juice, vinegar, whatever) before adding the oil. This give the salt a chance to dissolve before being coated in oil. And the acid also helps release the flavors of the aromatics.
This isn't to say that if you put everything in a jar at the same time and shook the heck out of it, you won't get an excellent dressing. But your arm may hurt with all that shaking. Peter's way is fast and easy, and I've used it ever since.