I see there have been several answers to your question so far, but I thought I'd add one little insight from my experience with SQF document control.
While trying to get ready for SQF certification, there were hundreds of documents I had to revise. I started with a standard format that I picked up from a consultant - a header on each page that displayed the company logo, document name, document number, version number, issue date, supersedes date (this was used to show the issue date of the previous version; if it was the first version, we entered "New Document" in place of a date). It looked like this -
(site location, if applicable)
1 of #
The "Code" or document number is just a unique identifier, so it won't matter to an auditor. But just as an example, here's how ours are set up - above you'll see **-***-#.### In place of the first two asterisks, we have a two letter code for the site (our company has sites in different locations, so we simply took two letters of the town name and used those). Then there's a dash for separation, and in place of the next asterisks, we used letters to identify the department (ex. QA for Quality Assurance, SAN for Sanitation, etc.). Then we had a unique numbering scheme - 1 was for policies, 2 was for procedures, and 3 was for operational forms. So the site policy would be numbered as 1.###, a procedure would be 2.###, and an operational form would be 3.###. The ### is just sequencial numbers 001,002,003 and so on, so each document has a unique number.
After all documents were revised in this format, we created a register (we used an Excel spreadsheet, with each department having a separate sheet). In the register, we entered every document name, the doc #, issue date, etc. This register was helpful when a team member wanted to verify that they were following the most up-to-date procedure or using the most updated version of a form. Whenever a document is revised, however, the dates and version must be updated on both the document AND the register, otherwise you lose your control.
Anyway, I hope that this was helpful for you and that I didn't make it to difficult to follow. Let me know if you have any questions.