Unqualified Offerings has good advice for students looking for work:
1) If your professor sends an email saying “I have been asked to recommend some good students for this job opportunity, please send me a resume ASAP so I can pass it on to my contact and put in a good word when I pass it on” the correct answer is “Here it is”, not “I’m not sure.” It’s fine to not be sure, but the whole point of applying is to keep an option open until you become sure one way or the other. You can turn down an offer that you don’t like, but you can’t get a job that you don’t try for.
2) Wait, you need to work on your resume? Don’t you have an updated resume on file?
3) When you send me the resume, don’t title the file “My Resume.docx”. The person making the hiring decision will have a folder full of resumes, and if they want to find your resume you should be making it easy for them.
4) For that matter, unless explicitly asked for a .docx or whatever, send a .pdf. Yes, people can take information from a .pdf and do stuff with it, but a .doc or .docx is much easier for the “lazy but malicious” type to modify. No, I’m not knowingly passing your resume on to a “lazy but malicious” type, but once a file is sent into the wilds of the internet who knows what can happen?
Also, there are all sorts of weird compatibility and formatting issues with different versions of Word. PDFs are much less prone to that sort of thing. And if you can’t afford Acrobat, never fear, there are free converters out there.
Incidentally, point 3 is especially good. Use your surname as the start of the file title!