Seriously, who really has a room completely dedicated to the occasional guest? Unless you still own your McMansion... you may be like the 99% (couldn't resist that timely political pun) that have to put grandma and grandpa up in the kid's room for Christmas or occupy the den/office.
You needn't completely stress out... nor should your guests feel like second fiddle. When you say "Make yourself at home" that doesn't mean fend for yourself ;) Take a peek at my AM Northwest segment on creating a Guest Room... it will help you work with the space you've got.
I hope you find my tips helpful...I can't take full credit... several of the tips were new ideas given to me by my facebook page fans and twitter followers. #muchappreciated ... and if you have some ideas we missed, please add a comment!