Right now I hear Shiner lapping water from his bowl, a flock of trainers heading out from the nearby Air Force base, Wrangler's nails tapping on the floor, and my live-in handyman opening the pantry door and mumbling to himself about breakfast.
All at once.
Yet if we're writing fiction, all the sounds our character hears would be overwhelming for the story. The same with everything she sees.
It's up to the writer to determine how to mix and match these sensory impressions to advance the story.
Sometimes we need to include everything, especially if we want to show how it contributes to the stress the character feels - as if the world is attacking her from all sides.
But most of the time one or two can describe our character's mood or add to the scene or build suspense without going hog wild.
Take the sounds I listed above.
These are all comfortable morning sounds to me. I hear them every day.
But maybe you're writing a thriller. The world is on the brink of war. The whine of jet engines would take on a whole different meaning. Counter that with the gentle lapping of water, and your character knows just how much she stands to lose.
A love story. Hearing her lover's mumbles reminds her of the words whispered in her ear the night before.
A comedy. Your character partied too hard the previous night and has a bad hangover. The lapping water is a raging storm at sea. Nails on the floor. Pounding. How much does that darn dog weigh? He's going on a diet!
And so on.
Listen . . . and be picky.
Your characters will like you for it.