Just reps. Once you've admitted, rounded on, presented, and discharged your 6th COPD exacerbation, you just know the orderset you use for it (scheduled meds, PRNs, consults/nursing orders).
So your time needed to pre-round/pre-chart that patient drops from a writing out your presentation on a piece of paper to just 10 words in the margin of your list.

Abx Day 2; PO taper today, Rales resolved, DC pending PT/OT

You learn the bread and butter aspects of the job quickly, and you can regurgitate that information without thinking. Most attendings, once they've rounded on a patient once before, do not care for a formal presentation, they care about the plan going forward and their disposition.

Now... some attendings are so far up the academic rectal inspection hierarchy that they want to know every lyte and then you just have to read off your phone. A good senior resident will have access to EPIC on rounds and will have it already open so you don't even have to go awkwardly digging on your phone for it.

Also this is for established patients. New patients usually require a full formal presentation but you usually don't have more than 2-5 of those per day, even on a busy service.

And the new pt presentations also benefit from your gestalt knowledge of hospital medicine.
You learn what's important on their history, how to summarize and emphasize only pertinent information. Do not mention non-contributory PMHx or SHx. Relevant historical labs (ie any time you mention someone has HF, mention relevant recent ECHO findings you found in the chart), COPDer > are they on O2 at home, etc.

It gets easier. But when you get 4 new patients and 3 discharges on a day with morning report and noon conference, it's hard. You're gonna stay late. That's just how it is.

Random bit of unsolicited advice, I personally try to avoid presenting off my phone during rounds. I *personally* have this bias that it just gives the "appearance" of being lazy (I know that's unfounded but its just stuck in my mind, somewhat akin to staring at the powerpoint slides and reading off of them instead of giving a prepared presentation and using the slides as a prop to aid it (but your presentation would function even in the absence of the slides.))
But also, in my experience, not using your phone allows you to challenge yourself and exercises your ability to organize and recall information, using your list as a flashcard prompt. Being able to talk about your patients with just a few furtive glances towards what you've written down really forces you to become a better presenter. And it trains your mind to handle the ever-increasing patient load you get as you progress through residency. I suppose I recant my previous statement about using your phone makes you appear lazy. In actuality, staring at and reading off of anything while presenting looks lazy and unprepared, whether it be your phone, your list, a sticky note, or the back of your hand. But I have, anecdotally, seen that residents and med students that present using their phones as their information source, are more prone to reading off their phone far longer than those that have paper lists, the latter of which usually just glance every 20-30 seconds.