Best format to send a attach a resume file to send in the Mail app for iOS (6S+)

I’m currently looking for work, and do a lot of job searching through Craigslist, as I have in the past. I’ve always run into this problem. I like to use the mail app because when you go to reply, you can just click the link instead of copying and pasting it, but when I go to send a resume, which I currently have saved in my Google Drive app on my iPhone, it doesn’t always work. Someone just asked me to send it as a PDF. What’s the best format to send a document through the iOS Mail app, so I can reformat it? Thanks for any help