For example, imagine a scene in which a character named Tom hands over his driver's license. A writer could choose to describe every bit of what happens, like this:
"Tom reached into the pocket of his jeans and pulled out his wallet with his right hand. He unfolded the smooth eel skin, thumbing through plastic cards to find the right one. With his thumb and index finger, Tom carefully handed his driver's license to the store clerk."
Or the writer could say: "Tom handed his driver's license to the store clerk."
Of course, when writing action, using strong, active verbs is important. Assuming you've chosen the right words, how many of them do you need? How do you decide how much detail is desirable? The process is like wading through a lake of words to fill a beaker of significant action. How do you decide what's significant? Ask yourself two questions: Is the action necessary to the plot? If not, does the action illustrate something the reader needs to know about the character?
Let's return to Tom and his driver's license. In many stories, this simple transaction is not going to be important to the plot. But what if the situation were different and Tom is traveling with a fake license, trying to cross the Mexican border and return to the United States? What if the person he's handing the license to is from Border Patrol? Then, perhaps, you might linger over each action, building the tension as Tom slowly, reluctantly pulls out that license, hoping that the forgery is good enough to fool the agent.
What if Tom's just showing his license to a store clerk to use a credit card? If the action isn't crucial to the plot, then all you have to do is get from Point A to Point B efficiently. But what if how Tom pulls out his license tells the reader something about the character? Imagine that Tom is obsessive-compulsive. The way he organizes his wallet and extracts cards in a particular order shows what Tom is like without the writer having to say it explicitly.
As you describe action, think about the purpose of the scene. Let the purpose drive how much and what kind of description you write.