Some people can write good directions and some people can't. I write directions and I write recipes. It's works really well to write your directions and then save it and go back a few days later and go thru them again. You're more likely to find your typos and missed steps that way. It also helps to have a friend or two to read them. Especially friends that aren't afraid to tell you "that doesn't make any sense and your math is a mess."