Having someone ask to see your résumé is a good sign that you're being considered for an interview. Respond to their request as soon as possible -- the sooner you send the résumé to them, the more top-of-mind you are as a candidate. Wait no longer than 24 hours at the most to send it. Treat the email like you would any other piece of business correspondence. Use correct spelling, punctuation and grammar, and keep your comments brief but informative.
Fill out the subject line so the recipient immediately know what the email contains. Treat this line as a "headline" for the email. Say something like, "Per your request: A copy of James Green's résumé to be considered for the position of vice president at WebsitesRUs.com." Leaving the subject line blank might get your email blocked by the company's spam protection software, and it also looks unprofessional.
Thank the person who requested your résumé for their interest. Start with a professional greeting, like, "Good morning, Mr. Jones," and write something along the lines of, "Thank you for taking the time to request my credentials, especially when so many candidates are interested in the position."
Explain what files you are attaching to the email, even if the only thing they have asked for is your résumé, and what position the résumé is related to. Include a statement like, "Per your request, I have attached my résumé outlining my job history." Give a brief description of the other attachments, such as saying, "A cover letter is also attached for your perusal," or "A separate attachment highlights the contributions I have made to my current place of employment."
Attach the résumé to the email in whatever format the person who requested it prefers. Limit any other files to one or two, and compress them as a ZIP file if they are large. Don't send too many attachments with the message: They can clog a recipient's inbox and cause problems when they open them. If you have a very large portfolio you want to show the recruiter -- such as graphic design layouts from a magazine -- upload the data to a third-party website. Send a link to the Web page in the email and explain to the recipient that they can view your work there at their convenience.
Thank the person who requested your résumé for their time. Tell them you look forward to setting up an interview on a mutually convenient date and indicate which method is best -- cell phone, email -- to reach you. Include a signature block at the bottom of the email that contains your full name, your email address, your phone number where you can discuss business privately and your fax number, if applicable.
Leave previously forwarded information in the body of the email. Recruiters are busy coordinating applicants for different jobs, and keeping this data in the message will easily remind them of what you are sending and what job you are applying for in case they have forgotten.