Welcome to your crash course on emailing professors! You're in college now, the big time, so to speak. That being said, there is a certain level of etiquette that should be put into place when communicating with your professors. Here are some things to keep in mind...
1) Use a telling subject line. Don't you dare leave it blank, and certainly don't neglect to keep it error-free. Your subject line should let the professor know the main topic of your discussion before they even open your email. Plus, if they think your email looks easy to respond to, maybe they'll get to yours first!
2) Use a salutation. The faculty, regardless of how caring and wonderful they are, are not your buddies. Show your respect with a greeting such as "Good afternoon" or "Hello." Be sure to then address them by the appropriate title and last name, e.g., Professor Williams or Dr. Smith.
3) Include a signature. Your email should end with a thank you, your first and last name and your contact information. The "sent from my Android device" auto-fill isn't going to cut it.
4) Don't ask for anything that can be found on your syllabus. I repeat: Do not ask for ANYTHING that can be found on your syllabus! This will only show the professor in question that you were too lazy to read the material that they spent time creating to avoid such questions.
5) Avoid sounding entitled. Your best case scenario is to never give your professor a reason to believe that your generation is made up of entitled brats. Take responsibility for any late assignment you submit, don't bring up "deserving" a better grade or an extended timeline and for the love of all things holy, leave your excuses at home.
6)Proof it! You definitely don't want to make grammar or spelling mistakes in your email. It doesn't matter that this isn't a note to your English professor, it just looks sloppy.
7) Don't follow up too soon. Social cues should indicate how soon "too soon" is. In the age of instant gratification, it can be tough to wait out a response from your professor. However, remember that your professor is teaching other classes and might have an inbox full of other emails to get back to before they can answer yours. Patience is a virtue!