Boil water with salt.
Add cut potatoes to water.
Cook for 15-20 minutes.
Check if fork goes in easily.
Drain water from potatoes.
Add olive oil to warm potatoes.
Add salt while potatoes are hot.
Let potatoes cool down completely.
Mix mayonnaise and mustard together.
Add vinegar to the mixture.
Add chopped dill to mixture.
Add celery and onion pieces.
Mix everything with the potatoes gently.
Add chopped eggs carefully.
Add more salt and pepper if needed.
Put in fridge for 2 hours.