1. Boil unpeeled potatoes (in salted water?) until just done (about ... minutes?), taking care not to overcook. Cool in cold water. Peel when cool enough to handle. Refrigerate peeled potatoes (in water?).
2. Dice bacon and fry until crisp; (drain on paper towel?).
3. Peel onions and apples. Dice onions, apples, and pickles and put them in a big bowl. Add olive oil, vinegar, light mayonnaise, and sugar. Mix well.
4. Cut chilled potatoes in half lengthwise, then into thin (lengthwise?) slices. Fold potato slices gently into the mixture in the bowl, taking care not to mash them.
5. Season to taste with salt, pepper, and a dash or two of soy sauce (not too much!).
6. Refrigerate for at least 30 minutes.
Generally good and understandable. Above is how I would write some parts differently, but your version isn't wrong.
A few tips and questions:
When listing numbered items, always use a period and a space before the next word:
1. Cook ...
2. Cut ...
3. Peel ...
Never more than one exclamation point (except in the comics).
Distinguish between 'cook' (any method) and 'boil' (in water), 'microwave,' 'bake' (in the oven), etc.
potatoes in their skins = unpeeled potatoes
cut into cubes = dice
put in the fridge = refrigerate, chill
BE gherkin = AE pickle
'Fridge' is too casual; in writing, use 'refrigerator.'
'Steep' is usually for tea; here you could say 'marinate' (if there's a lot of vinegar) or just 'let stand.' Since it's in the refrigerator, 'chill' is really enough.
Bacon in the US usually comes in thin slices, not thick slabs, so you can't really make cubes; you could say 'dice' or just 'cut into small pieces/squares.'
Where are the quantities? How many potatoes, onions, apples, pickles, slices of bacon? How much olive oil, vinegar, mayonnaise, sugar? The ingredients can all come in a list at the beginning, and for potato salad it doesn't have to be very precise, but you need to give some idea. Be sure to use English measurements (cups, pounds, teaspoons, etc.).
How long do you boil the potatoes? In salted or unsalted water? How can you tell when they're done but not overdone -- stick in a fork?
Why peel 'and clean' -- do you mean wash, and if so, why is that necessary after they're peeled? Do they need to stay in a bowl of water in the fridge so they don't turn brown?
When do you add the bacon bits -- do you sprinkle them over the top before serving, as a garnish, or do you add them to the mixture in the bowl before refrigerating, or some of both?
Sounds tasty, except for the pickle ... (-: