Is there any way to reduce the size of my dome packed up for storage or transport?
Yes; you can use a house vacuum to compress your packed dome to about 1/2 its volume; roll and pack up your dome as in the instruction manual; warp in its wrapper it came with; tape the long seam of the wrapper; tape any holes in the wrapper. twist one end tight and then fold and tape this twisted end to the package; insert your vacuum hose in the other end twist and tape it tight; turn on your vacuum; with the vacuum on push on the package and it will compress to about 1/2 its original size; now tape around and around your package with the vacuum still on (this is to hold the package compressed when you remove the vacuum. now remove the vacuum and tape the end of your package closed.