If you don’t want the ribbon to show up in your InfoPath form, with the form open, click on File and then click on the Advanced form options.

When the Form Options dialog comes up, notice that, when the ‘Web Browser’ category is selected, under ‘User Interface Options, there is a checkbox to ‘Show InfoPath commands in Ribbon or toolbar’. If you leave the box unchecked, the ribbon will not show at all.

You will also see that you can control which buttons appear in the toolbar, should you want it left turned on. For instance – – if you have a fairly large form, you may want the Submit button to appear at the top, to match a submit button at the bottom. There will be Cut/Copy/Paste also, but the ‘Save’, etc buttons will not show.