You can use the 'Resume Manager' to store multiple versions of your resume in your portal. When inside the 'Resume Manager' just click on the 'Add New' button and enter a name for your new resume. A name that easily identifies the position you will applying for using this resume version will be the most helpful. After entering a name you can then create a new resume from scratch or upload any existing version you may have.
Most resume types are supported (Word, PDF, html, etc.) Typical file uploads are that of Word or PDF.