One of the most important things to consider when you sit down to write something is how to choose a writing style. The writing you style you use for any given project will depend on a number of factors including your own ability, the audience that the writing is intended for and the purpose of the writing. By understanding each of these items you can better choose the correct style of writing.
The first thing to consider is your own ability. You need to write in a style that matches your strengths. If you are an excellent comic writer, it is probably not a good idea to try to do informational writing without some practice and some training. If you are great informational writer, it is a very different prospect to sit down and try to write fiction. Know your own limitations when it comes to choosing a writing style. Be ready to study and practice a bit before you write outside of your normal writing style.
The next thing to consider when you set out to choose a writing style is to consider who the writing is intended for. If, for example, you are writing for a general internet audience, you want to write in a conversational style that avoids intense and difficult jargon. If you are writing for a younger audience you will want to make sure that you are using words that are age appropriate. In contrast, if you are writing for an audience on a technical topic, you will want to make sure and use the types of technical terms and constructs in your writing that your audience expects.
The final thing to consider when choosing a writing style is the purpose of the writing. If the writing is intended to be used as an instructional manual you'll want to write in an instructional style. You'll want to write in very succinct and direct step oriented paragraphs. Each paragraph should describe a single step involved in the process, for example. On the other hand, if the intention of the writing is to sell a product, you'll want to write in a compelling style. You will want to use active words and you'll want to use all sorts of descriptive tactics. You want to get your reader to actually believe that they can sense, feel, smell and hear the product that you are trying to promote, or the results of that product or service.
In the end, it is not particularly difficult to choose a writing style. You just need to address these three areas of concern which will help you to choose the correct writing style.