The Description guide will help you to write descriptively. Unfortunately, there is no set in stone formula on how to integrate descriptions. You will need to "feel" for it, and writing descriptions requires some sort of inspiration. It is also recommended to use a thesaurus to find new words.
In the end, it just takes practice trying to balance what should be enriched with fluff and what should be straightforward.
Showing versus telling
You may have heard the phrase "show, not tell". First, there's the plot and story. However, just that alone may not be enough to draw the reader into it. By incorporating descriptions, you can enrich your writing and draw other readers into your world.
Good descriptions are stimulating to the senses, allowing the reader to become a part of the world. It is ideal for narrative writing. However, in informational articles, the facts should be straight to the point as the purpose it to get information.
Metaphors and similes can draw the reader into the world:
"The sun and sky were red, and there were mountains in the back."
"Resting motionlessly in the sky was a glimmering red dwarf sun that illuminated the sky with crimson and orange. At the edge of the horizon, mountains towered high above the pink, grassy plains that led up to them."
Even just replacing words with different synonyms will make your writing sound better:
Description versus wordiness
The bare, blunt sentences of a story are the skeleton. Descriptions are the meat. However, wordiness should be avoided at all costs. If there is a paragraph in your story that is wordiness (or just fluff), it does not add to the story. It only slows it down.
Description versus pace
Keep in mind that the amount of description should not stall the pace of the story. The best time to write descriptions is that the beginning of a chapter or story. Describe enough to get the reader to understand what the setting is, and avoid repeating descriptions when the setting changes.
If a character glances at something, the description should be as long as it is to read as the character looks at it. The amount of descriptions would differ between two characters staring at a sunset or one character briskly walking past a store.
Conservation of detail
While we do enjoy having a largely detailed shared universe, in writing stories, you should only include details that are necessary for the plot. A playwright named Anton Chekhov stated that if there is a rifle on the wall, it must go off later in the play, or else it shouldn't be there. This is known as Chekhov's Gun, and it is considered a vital necessity to avoid a Deus ex Machina.
False Chekhov's Guns are often known as red herrings, though it is considered difficult to use these effectively. The reason why red herrings are discouraged is because most of the time, they do not do much other than pad the length of the story, and are ultimately unnecessary for the plot.