I started because a coworker named Theo kept leaving a meditation app icon visible on his home screen during meetings, not because he ever said a word about it to me or anyone else. I noticed it for weeks before I actually downloaded anything myself.
Your first day
Sit upright somewhere quiet for five minutes. No cushion or app required, a chair and a phone timer set before you start are enough. Spine straight but not rigid, eyes closed or gaze soft and down. Breathe normally, not deeply or slowly on purpose, since forcing the breath just gives you one more thing to manage. Count each exhale silently, one through ten, then start over at one. If you lose count, start again at one.
When you lose count or drift into a thought, which will happen constantly at first, don't treat it as a failure worth getting frustrated about. That reaction is actually the entire practice working correctly. Noticing the drift and returning to one is the skill, not staying uninterrupted the whole five minutes.
The thing most people miss
The return to counting after a distraction is the actual exercise. The mind wandering is expected, and catching it is the repetition, which is why a session full of interruptions can still be a good one.
Once I stopped getting annoyed every time I lost count around six or seven, the sessions immediately felt less like a test I kept failing, and the sits themselves stopped dragging the way they had the first couple of weeks.
How you'll know it's working
The tell isn't fewer distracted thoughts during the five minutes. It's catching yourself breathing shallow during a stressful moment somewhere else entirely, and consciously slowing it down the same way you've been practicing on purpose.
A coworker asked if something had changed after a meeting that would normally have rattled me, because I seemed calmer through the whole thing. That's a stranger measure of progress than anything that happens on the cushion itself. Body scanning, noticing physical sensation region by region instead of counting breaths, is the same underlying skill turned toward the body next.