There are a variety of way, but mostly it depends on the App you used to create the Resume. If the app has the ability to open it's files in other apps, it will probably offer iCab as an option. Look for an icon that looks like a box with an arrow coming out of it. This is the usual hiding place of share/export options in an app.
Another possibilities include emailing the document to yourself, and using the Open In options from email (tap and hold on the attachment for options).
If your resume app can save to DropBox, you should be able to access Dropbox from iCab and download it there. Once downloaded, you can upload.