1) Details. Look at the opening of this story and notice how the author incorporates precision and detail in showing the texture of his world.
The last shot fired in the Battle of Chametla hit Private Arnulfo Guerrero in the back of the head. It took out the lower-right quadrant, knocking free a hunk of bone roughly the size and shape of a broken teacup. This shot was fired by a federal trooper, who then shouldered his weapon and walked to a cantina on the outskirts of town, where he ate a fine pork stew with seven corn tortillas and a cup of pulque. The shot was witnessed by Guerrero’s best friend, Corporal Angel Garcia, and by Guerrero’s dog, Casan. Casan was a floppy-eared Alsatian he’d stolen from a federales base the year before.http://www.tinhouse.com/magazine/current-issue.html
2) Motivation Response Units. It isn't enough to show the action. We need to see the character's reaction. Learn more about MRUs here:
Example 1) Just the action.
The tiger dropped out of the tree and sprang toward Jack. Jack raised his rifle and fired a shot. The bullet grazed the tiger's left shoulder. Blood squirted out of the jagged wound. The tiger roared and staggered, then leaped in the air straight at Jack's throat.
Smooth, easy to read. But missing something.
Example 2: Action plus character response
The tiger dropped out of the tree and sprang toward Jack.
A bolt of raw adrenaline shot through Jack's veins. He jerked his rifle to his shoulder, sighted on the tiger's heart, and squeezed the trigger. "Die, you bastard!"
The bullet grazed the tiger's left shoulder. Blood squirted out of the jagged wound. The tiger roared and staggered, then leaped in the air straight at Jack's throat.
Very different. In the first one, it is like we're observing the scene. In the second, we feel it.