The story itself isn't bad, but the creepiness is greatly diminished by the monotony of the sentence structure. Vary the length of your sentences, and try not to start most of them with "you." (God, I sound like a grammar teacher.)
"Omg. Where did they get the idea to not use army guys? Are they taking drugs?" --Tim Schafer on originality in videogames
Nice lil story. Tho i personally didn't find it scary. As noyb said, try to limit the number of times you use the word "you". If you stare at the giant paragraph from a afar, you'll notice that all the "You" bits stand out. Pretty cool
Some of what you need has been said already, so I'll just repeat everything you've all said, but with more wordiness :
- Whitespace. Use returns, paragraphs, line spacing, etc.
People often don't realise, but the physical layout of your words on the page can be as powerful as the words themselves.
Our thoughts don't come out in one thick body of words, they form groups, have pauses, etc. For example:
With the dull thud of rubber boots, Simon and his friends stepped onto the deck. He gave orders, and the group dispersed. As the men paced noisily overhead, the occasional plank would shift and splintery dust would trickle down.
They were after us. But they weren't going to succeed. We had been through too much together for me to be shot and Klara to go back to Auschwitz. They wouldn't be allowed to win.
That example's not a great little composition, but hopefully you'll agree it'd lose any sense of humanity if it weren't for the paragraph breaks. They give it pace.
- Sentence structure. While the whitespace sets the pace of thought, sentence structure can also achieve this. You can use it to convey action. Punchy action. Action with people getting punched. And stuff.
You can also add variation. This comes from reading other peoples' works and getting ideas on how other people form sentences.
- Word Choice. There are so many words to use it's wonderful! Long words can give ponderous desriptive meanings to thoughts. On the other hand, there may be a much shorter, simpler way of saying what you want to. 'Dash' for example, is often a better choice for action scenes than 'to run quickly'.
I've seen sentences before where someone says "very quickly, we ran for the door" when they could have just said "we lunged for the door" or "we made a dash for the door" or even just "we dashed to the door".
- Description. This is an important one. In order to drag the reader into your fictitious world, you need to describe things in vivid detail, without clogging it up. We do this the same way as the movies do.
Think of it like The Lord of the Rings, when they enter that enormous cave with columns stretching as far as the eye can see. We get the grand music and panoramic sweeping views as everyone looks in wonder. THEN all the orcs appear and they get chased, blah blah blah.
Imagine if they came into the room, started running from the orcs, and half way through the action, suddenly, we get the panoramic views and the grand music.
See what I mean? Do the description when the scene is peaceful so that by the time we get action, the reader already knows what the setting is like. So if we're 'dashing for the door', the reader should already know that it's made of rusting metal, with yellowy flakes peeling like the skin of an iron leper.
- Other than that, read the works of others and think of how they do these things. The more you read, the better your writing will become.
This example shows something about description, word choice, sentence structure, pace, etc. For this, the reader should by now already know that the two characters have sought refuge in a dark, murky cave - which for some reason is filled with furniture, as if it used to be used by a band of smugglers. As usual, random people with german accents are chasing them with torches. Scareh
"The flashlight was hovering, working into the cracks of the cave, past the piles of furniture and slowly nearer to where we hid. No sound. One breath could be fatal. We stood there like corpses, pressed hard together, our faces cold. A shaft of light finally settled on Klara's cheek.
The game was up.
We raced out and I threw a punch into the darkness - a lucky punch. There was a sharp German cry and the flashlight clattered to the floor. With a great commotion, more flashlights started to appear at the mouth of the cave. There wasn't much time - any minute now, the cave would be flooded with light, and we'd have nowhere to hide.
I looked over to Klara beside me. The glimmer of distant torches was sparkling in her eyes. And those eyes looked sorrowfully into mine.
The lights got brighter, closer. We kissed. And then they were upon us."