Description is an important part of fiction. You have created a world in your head, now you have to get it into your readers’ heads. You do that by description. Description is more than how something looks. You have five senses, so do most of your readers. Cater to all five senses.
You need to describe what your characters see, but don’t forget what they hear, smell and feel. If they are at the seashore, remember that the ocean has odors, salt, fish, seaweed. They all have an odor. Is your character close enough to feel the Spray? Describe how it feels. What doe the seagulls sound like? Describe it. Can your characters taste the salt on the wind? Yup, describe it. This will make the experience better for your readers.
That is the goal — to make your readers feel that the story is real. Use your five senses to describe the sensations your character might feel. To do that well, describe they hear, smell, taste, feel as well as what they see. That’s not to say you need to overload your reader with the sensations of your character. It’s a fine line between good description and overkill. You don’t want to put either your character or your reader into sensory overload.
Let’s go back to the seashore. We have a character, Jane, walking along the beach. We want to capture the essence of the sea shore. The sand shifted under Jane’s feet as she walked. The salty wind whipped her long hair across her face. Seagulls screamed at her. She moved closer to the water where the damp sand made walking easier. Glancing back, she saw the water erase her footprints. She licked salt off her lips. The sea filled the air with the scent of salt and seaweed. She began to jog, feeling invigorated. Ahead, small crabs raced from the sand to the water or buried themselves in the sand as the tide went out. Jane stopped to tighten a shoelace, gritty with sand.
That’s sensory overload. There’s too much there in such a short passage. However, the sense of the seashore is there. If we added more of Jane’s thoughts or actions into the passage, we could dilute the sensory overload. There is a better way to describe the scene.
Jane walked over the shifting sand to the mudflat. Bending down, she tightened a sand encrusted shoe lace. Then she began jogging along the water’s edge, seagulls screaming overhead. Salty seaweed scented air invigorated her as she increased her speed. Water lapped at her shoes, splashing salty water on her shoes and pant legs. Crabs evacuated the space before her as she ran. She paused at an outcrop of rocks to catch her breath. Then she turned and ran back the way that she’d come, leaving new footprints on the mudflat, where the water had erased the signs of her passages. It was time to confront Chris.
You don’t need to engage all five senses in each scene. All you have to do is use at least two, three is better, but two will do. That will give a sense of realism to the passage for your readers. If you can do that, your readers will love you for it.