First, place your peeled and chopped potatoes in a large pot, then fill the pot with enough cold water to cover the potatoes. Add a good pinch of salt.
Bring the water to a boil over medium-high heat and let the potatoes boil until they're tender when pierced with a fork, about 10 minutes. Once the potatoes are done, drain them and set them aside to cool.
In a large bowl, add the mayonnaise, mustard, sweet relish, and vinegar and whisk until combined.
Add the diced onion, celery, chopped eggs, and cooled potatoes to the mayonnaise mixture in the bowl. Season the salad with salt and pepper to taste.
Arrange the sliced boiled eggs on the salad, then sprinkle with paprika for garnish.
Cover the salad and refrigerate it for at least 2 hours to allow the flavors to meld.