Use of "Preview"
ALWAYS, and we mean ALWAYS, use the Preview feature to check on your edits before committing them. Do lots of edits and then save, not lots of saves while you edit.
To find out what markup you can use in addition to the stuff available from the sidebar and Editing help when editing, see the Wikipedia Cheatsheet page for now, which is the MediaWiki syntax and formatting help page. New pages specific to [Main_Page|The Transport Tycoon Wiki] will be created and linked in the nick of time.
Use of the Summary field
When editing a page, put something helpful in the "Summary" field (when you go to make an edit, it's directly beneath the big edit box - see?) to make it easier for all concerned to see who did what at-a-glance. The idea for the comments list is that someone can look at a version comment, and establish without having to look at individual diffs and comparisons to see what changed between versions. It also facilitates transparency, one of the reasons why Wikis even exist.
Examples of useful comments:
Fixed some typos. (Tells us what you did) Expanded upon first paragraph. (Tells us where you did it) Removed obsolete information about Thisthat & Theother, plc. (Does exactly what it says on the tin) Updated revision dates. (Brief, but hopefully there won't be much of those on the given page to be updated)
Examples of not-so-useful comments:
(Empty comment - people have to check the diffs for each version) Written by xyz. (You don't say? It's not as if the "history" list already shows who wrote it ...) Added more information. (Oh, well isn't that helpful? Tells everything doesn't it?)
Be warned -- if you do not include a useful comment with an edit, that page may be rolled back and your edit UNDONE.