Building on some previous thoughts on improving your writing, I wanted to jot down a few ideas and tips that I have been thinking about since the last post.
Drill apostrophe rules in your head. Apostrophes are used to show possession, letters ommitted in contractions, and a few other obscure uses. This link shows proper use of the apostrophe, and a few minutes is all you need to become an expert. If nothing else, remember that "it's" always means "it is," and is never used as a possessive pronoun.
Keep submitting material until someone accepts it. Yes, rejection letters can be painful, but every published writer can tell you horror stories about rejection slips. Collect them as merit badges, and don't let a harried editor's rejection (or non-response) get you down.
Being a good writer means being a good reader. Subconsciously we model our writing after the material we read. If your domain of literature is limited to Danielle Steele novels and the daily paper, you are limiting your exposure to material that might inspire you.
Remember the "rule of three" in seriated groups. There is a natural rhythm to groupings of three items; listen to the difference in "apples, oranges, and pears" as opposed to "apples, oranges, pears, bananas, lemons, and limes." This does not mean that every series should be groups of three items, but maintaining some sense of rhythm is important in almost every genre of writing.