Let's think about the first line of the story:
At the lake shore there was another rowboat drawn up. The two Indians stood waiting. (1)
Wait, what do you mean another rowboat? So there was already a rowboat? How are we supposed to know that?
Oh. You see what Hemingway did there?
By talking to us as though we are already somehow familiar with the scene, Hemingway treats us like we already know what's going on. In turn, we feel like we already know what's going on. Right away, familiarity is fostered. By treating us this way, Hemingway is able to tell us everything we need to know about the scene by using subtle devices. To understand this better, let's consider the excerpted lines from the story right above.
If there is another rowboat, we know that there are two rowboats. And we know that they were expecting the two Indians to be waiting because they are the two Indians, instead of just "Two Indians stood waiting." See how important the article is there? Hemingway uses them all the time to foster a sense of familiarity, so be sure to keep your eye out for them. They're one of the ways Hemingway positions his readers to feel like they're already part of the scene and contribute to the familiar tone of the story. Hemingway writes so seamlessly that it's easy to just go along for the ride, taking the scenes in as they come.
This is a word that gets tossed around a lot whenever Hemingway is in the mix. It essentially means that you're probably never going to come across a ten-dollar word in a Hemingway story. But that's just at the level of diction; it also means that you're not going to get any Doestoevsky-esque internal monologues that go on for pages and include four sentences total. What you will get is a lot of short, descriptive sentences that are meant to contain everything you need to know about a character, a scene, or an action. For instance:
Inside on a wooden bunk lay a young Indian woman. She had been trying to have her baby for two days. All the old women in the camp had been helping her. (10)
How does Nick know all of this? Presumably someone told him, but we don't get to see him being told because that would take up valuable page space. Instead, Hemingway just assumes that we're sharp kids and we can follow along.