Although reflective writing is more casual than other types of academic writing and does not usually require extensive research and citations, it will be held to the same standards as any other type of writing in terms of punctuation, grammar, clarity and logic. Don't get sloppy. Take the time to reflect in depth on your metacognitive processes -- not just the facts you have learned, but the way in which your mind analyzed and organized these facts. After you've written a first draft, reread it with an eye to uncovering deeper layers of insight and previously unseen connections. And be honest. Insincerity is often easy to spot and makes the entire exercise pointless.