1. Dress for success. You don't have to overdress, but match the situation. Depending on where you will be determines whether you need to be business formal or business casual; slacks, dresses, or jeans; ties or jackets. However, remember this - you won't go wrong being slightly overdressed. The other way can lead to embarrassment. If in doubt, always ask!
2. Make your mother proud. My mother drilled table manners into me. Fortunately for me, they stuck. Make a habit of understanding table etiquette all the time because it's easy to slip into default mode at the worst possible time. Nothing says "blown opportunity" like using your fingers to scoop food on your fork.
3. Make your English teacher proud. I was at a recent business event where the speaker used improper syntax. Doesn't come across well when you're supposed to be the smartest person in the room. Know the difference between "good" and "well," "them and "their;" and a host of other common gaffes.
4. If you're writing, please know that "lose" and "losing" is never spelled "loose" and "loosing." And "alot" is NOT a word; it's "a lot." Please. These errors are exacerbated in writing. Oh, and remember that punctuation always goes inside "quotation marks." (here is an example) 
5. Send thank you cards. Another "Mom-inspired" courtesy. I don't mean email, either. I mean a real live, found in the mailbox thank you card. It sets you above the crowd because it so rarely happens.  

You never know who is observing you and what pull they have in helping you attain success in business. You can also help your children out by teaching them this simple recipe. I have my mother to thank...you probably do, too! Your biggest takeaway should be that by observing these rules, you can't go wrong. That, in and of itself, should be a recipe for success!