Autosave?

Pages version?

MacOs version?

It is nice to know the answers to those questions as the answer will differ depending on your answer to the questions.

This is what the Help online says. Always start you document by saving it once.

Save or rename a document

Pages automatically saves your document as you work so you don’t have to. You can rename your document, create different versions of it, and save it to another location.

Save a document

Pages gives a new document a placeholder name such as Untitled 1 and saves it to a default location. You can specify a title for the document and save it to a different location.

1. Choose File > Save (the File menu is at the top of your computer screen).
2. Enter a name in the Save As field.
3. Enter one or more tags if you like.
4. Choose where you want to save the document.You can save it to a folder on your Mac or on a server, or save it to iCloud.
5. Click Save.

When you save a document to iCloud, it appears automatically on your iPad, iPhone, or iPod touch (if you set up iCloud) and updates whenever you make changes to it on any computer or device connected to your iCloud account.

The Aoto save is really biult into the MacOs system and not in the Pages application. I am not using Mavericks as I find Snow Leopard iss working well for me. as far as I know you can't the time span. Ask in Mac OS & System Software Mavericks forum about it.

There might be a third party applications that can do it for you like ForEversave but I don't know if it is compatible with Mavericks.