You didn't tell what's game you are making, i guess it's platform
Add a webstorage.
Create an invisible sprite like a helper could act like checkpoint, place checkpoint sprite on specified place should autosave.
Make an event collision between player and checkpoint sprite, add webstorage value to player position. Then add on start layout with condition webstorage exists, it could load the checkpoint on specified position.
Check this out and download .capx you need to modify it:http://www.scirra.com/arcade/example/1460/save-load-engine-for-platform-games