what can I do to protect my MacBook Pro

I would just use the black cloth that came with your MacBook ,just place it on the keyboard when you close it and when not in use. Also get a nice case type sleeve to keep your MacBook in when not using it .

Do not use palm rest or keycap covers on a Mac notebook with a Retina display - Apple Support

Hi,

Why you think you can't use keyboard cover? I've been using keyboard cover as well as screen protector.