A sure fire way to have the best potato salad around is to have it nice and creamy, so that they'll want to lick the bowl!
In my potato salad, I like to put potatoes (duh), diced boiled eggs, canned diced carrots and peas, fresh ground pepper, sliced red onion, mustard, mayo, a little bit of yogurt, and relish, and combine it all well.
Now, how do you make it creamy? It's not the eggs, and it's not the mayo or yogurt. It's the potatoes!
When you are boiling the potatoes, make sure you OVER boil them, to the point that they're starting to crumble or fall apart. This way, they will meld into all of the other ingredients as you are mixing. Then it'll be nice and creamy :)