HeeHee! As big as you can make it. I have a friend who has a big ne and she has it set up with a small kitchen so she can make coffee and tea, warm up something in a small microwave, etc. She also has two comfy chairs so her hubby can come and watch TV and visit with her while she is sewing or doing hand work. She has a special spot for all her sewing machines because she invites gals over for a sewing fest. She has a large walk in closet for all her fabric and big bookshelves under a window for all her books. she has a blanket on the lower shelf where a heat vent is so her kitty can sleep there anytime she wants, which is often. Big design wall also. Jan