One space after a period. I am always surprised when I read the manuscript of a new coaching client or when I work with a new freelance writer and his or her copy has two spaces after each period. Gosh, I haven’t put two spaces after a period since I typed my college term papers on my handy-dandy new typewriter (the one with the cool erase ribbon!). With the advent of personal computers and desktop publishing, the two-space rule went bye-bye, so try to remember, if you can. It’s one of those things that dates you as a writer.