In order to write well, good observation skills are a must. This is especially true when writing fiction. You need to be able to accurately observe people and events around you if you hope to convey realistic descriptions to your readers. We all are aware of watching a scene in a movie or reading a book where the setting, description, or words spoken by the characters just looks off. In many cases, this is due to the writer omitting important details in his or her descriptions, which make the scene seem false. If you want your writing to seem real, pay attention to the real life around you so you can portray it accurately on the page.
But being a good observer is only part of the skillset that a good writer must master. The other thing that the writer must have is the ability to accurately convey his observations to the world in a way that enables the reader to feel as if he were looking at the scene himself. This means that a writer must have a superior command of the language — both the words used to describe people and things and the words needed to bring those descriptions to life.
For a writer just starting out, it may seem that there's a long road to travel before he'll attain all of the skills necessary to become a master of his craft. And he's right. But the length of the road is going to be the same whether it starts today, tomorrow, or a year from now. And that's why the most important thing that an aspiring writer can do is to begin writing today and to keep on writing — even if he has no current writing project.
Daily writing exercises help you to hone your writing craft in a couple of ways. They show you where you're weak and where you need more work and practice. Also, constant writing will eventually lead you to where your true interests are, so giving you a natural path to follow.
Many people have a natural creativity and storytelling talent. But, in most cases, talent is not enough. Most professional writers will tell you that the most important asset they have is the ability to discipline themselves. They are able to devise and maintain a writing schedule for themselves until they achieve their goal. Whether their goal is 5 pages a day, 1 chapter a week, or some other guideline — they set their goals and try to make them. And even in cases where, for some unforeseen reason they are unable to meet their self-imposed goals, because they made the attempt, they're much further along than the dreamer who did nothing during that same period.
Another trait that you have to master, if you want to become a successful writer, is the ability to take criticism. Other than acting, there are few professions where rejection is such a natural part of the territory. The trick is to learn good criticism from bad. Then simply ignore the bad criticism, and learn from the good criticism.