How To Extract Stories From Experiences

Perhaps one of the biggest myths purported in the writing community is that it is absolutely imperative to have a wild imagination. While a lil' imagination certainly spices things up, creativity is all you really need. But first, you must identify the raw material available to work with, then quickly follow up with a generous dose of creativity to turn Pinocchio into a real boy. And that raw material is you.
Now, don't be alarmed, we aren't gonna put you through a processor or anything. The things stored up there in that noggin of yours are yours alone to extract and utilise, at your leisure. Not the whimsical dragons and unicorns, but everyday life and its minutest details; everything your brain has stored away "just in case".
That'd be a lot of material to sort through so here's something to help you narrow down precisely what you're trying to find in that mental attic of yours. Dive in, it's time to dust away those cobwebs.

1) Write what you know
If there's one tip you'll see reiterated time and again, is that it's easiest to write about what you know; often, these writings compose some of the most authentic pieces out there. Most authors recommend depending on familiar things for inspiration; be it emotions, incidents, locations, experiences. If you can call it your own, then you can very well write about it. If you can write about what you once experienced, you will be able to channel your inner Jiminy Cricket and breathe life into your characters.
This process, while extremely beneficial when trying to lend a story a more human persona, has another slightly more selfish benefit: catharsis through character. If you've ever felt emotions you didn't want to process or gone through things you'd rather not think about, I recommend writing them into a character's life and getting it out of your system. Not only will this allow to process what you're writing at a slower, deliberate pace but will also lighten the load you once carried, for your character will lend a helping hand.

2) Extremes are easiest...
The easiest emotions to gift a character, while drawing from your own experience,are the extreme ones. The extreme highs and the abysmal lows, the ones whose sheer magnitude overwhelms you. There's simply so much of them that the cup of creativity runneth over; you'll find words and ideas flowing onto the paper like manna from heaven. The best bit is that you can use these same emotions repeatedly in different stories, for different characters and still have enough to call your own.
However, often when we sit down to write, we can't recall a single instance where we felt anything but this pesky writer's block standing stubbornly between us and a good story. There's a way around this block but it takes two things every word ninja has to master (is this cultural appropriation, I hope not): vigilance and diligence. Yes, they rhyme. No, it wasn't intended. Bear with me.
Sometimes, scratch that, most times the extremes in our life sneak up on us; their suddenness is part of what makes them so jarring, so significant. Like when your childhood pet died and no one saw it coming. In moments like these, it's hardly human to expect one to be in any shape to churn out a story but here's what you can do. Write precisely what you're feeling; it needn't be proper sentences, heck it can even be a collection of adjectives. But as soon as you're able to, note it down and save it. That way, when you're struggling to pen genuine emotion, you can refer back to your own notes and voila, problem solved.

3)...But boring can be brilliant too
If you think about it, a lot of a story (especially novels) are chock-full of the characters indulging in the most mundane of activities: brushing their teeth, tying their shoes and whatnot. Yet, these mundane instances often exhibit one's proficiency as a story-teller. For why would a reader keep reading if the story bores him? It's not like you can do away with these activities entirely and pen a story composed purely of adrenaline. We could call them a necessary evil, but that doesn't quite fit; they're soothing, reminding the reader that the character is actually human in every sense of the word, allowing the story to breathe.
So how do we tackle these so-called boring bits? At the risk of repeating myself, once again practice makes perfect. Pay attention to the boring lulls in your own life and take mental notes if actual notes are too much effort (just pretend you're texting a friend and write it down, future-you will thank present-you). Did a bird crash into the windowpane during class, giving you the heebie-jeebies but no one else seemed to notice? Did you spend five whole minutes trying to squeeze toothpaste out of the spent tube because you couldn't be bothered to forage for a new tube? Or perhaps you brush your teeth twice before important meets, for that extra-shiny, extra-minty, extra-fresh good luck. What might seem commonplace to you might be completely incomprehensible in another's book. The world is a lot less "relatable" than you'd expect; one man's "boring" is the second man's "brilliant".

To summarize, introspect often and be as self-aware as possible. If even two percent of thinks "Hey, maybe I should write this down" then you definitely should write it down. Give these tips a whirl, decide what works for you and how you can optimise it to best suit your writing. The possibilities are limited only by your own effort; in theory, they are virtually limitless. Write yourself into the story if that's what it demands, but keep writing.