Here's a few methods you can use to your liking;
1. Open Excel. Go To Tools>Options>General. You will find a text box titled Default File location showing the path to the default My Documents Folder. Just change the path to point to a folder of your choice.
2. To change the location of My Documents Folder, right-click on the My documents icon on the desktop and click on properties. Click on the ‘Move‘ button and select a new location. Now, whenever you double-click on the My documents icon, you will be taken to the new folder.
3. MS Word- Open MS Word. Go to Tools>Options>File Locations. Select ‘Documents’ under ‘File types’ and click on Modify button at the bottom. Now choose any folder in another drive to which you want the files to be save by default.
Hope this helps,
Don