How do I save a Keynote document to cloud

Hey there QuJing,

It sounds like you have a Keynote presentation that you would like to save to iCloud, to open on your iPad. You can do that in the File menu:

On your Mac, open the presentation you want to appear in iCloud, then do either of the following:

• For an already-saved presentation: Choose File > Move To, then choose iCloud from the Where pop-up menu.
• For an unsaved presentation: Choose File > Save, then choose iCloud from the Where pop-up menu.

Keynote for iCloud beta: Sync a presentation across your devices

http://support.apple.com/kb/PH12853

You can verify that your Mac has is setup correctly with this:

Set up Keynote to use iCloud

1. Open System Preferences on your Mac, then click iCloud.
2. Sign in using your Apple ID, or request a new Apple ID and then sign in.
3. Select the Documents & Data checkbox, then click Options.
4. Select the Keynote checkbox, then click Done.

Use iCloud with Keynote

https://help.apple.com/keynote/mac/6.2/#/tan79be8e93

And on your iPad with this:

Set up Keynote to use iCloud:

To use iCloud, you must sign in with your Apple ID in the Settings app, and make sure iCloud is turned on in Keynote.

1. Tap Settings on your Home screen, and then tap iCloud.
2. Sign in using your Apple ID, or request a new Apple ID and then sign in.
3. In the list of iCloud services, make sure that Documents & Data is turned on.If it’s not, tap Documents & Data, and then slide the switch to ON.
4. Scroll down to Apps on the left side of the Settings window, and tap Keynote.
5. Slide “Use iCloud” to ON.

Keynote for iOS (iPad): Keep presentations up to date across your devices using iCloud

http://support.apple.com/kb/PH3495

Thank you for using Apple Support Communities.

All the best,

Sterling