First things first...the yard. Save up your money and collect a menagerie of insane animals. Must-haves include a raccoon that never stays in your own yard, peacocks that yelp at all hours of the night and make it so that the neighborhood actually creates a new rule against peacocks as pets. Purchase a pet zebra who you'll eventually have to return because he will kick and act completely wild. Buy a wombat, and name it after the husband of the woman you're having an affair with. And joke around about purchasing an elephant to wash your windows and bring in more income from passersby who want to buy a painting from such a strange man.
Rossetti's actual home on Cheyne Walk.
Inside your house, make sure you have about ten thousand things that you collect. Collect numerous obscure musical instruments, both for use in your paintings, and also just to sit around never being played and looking lyrical. Fill your house with tons and tons of mirrors, (seen in the top painting of Rossetti sitting in his home) strange antiquities, and of course, like William Morris, plenty of blue and white china.Three pieces of china from Rossetti's actual collection.
Finally, and very importantly, the bedroom. Make sure your bedroom is extremely dark and depressing, with curtains around an ancient bed that never let in light or air. The fireplace in the bedroom should be large and stifling, with more of your collection of china, brass, and knick knacks above it. The most important thing is to feel completely unable to breathe in this room, with no breeze able to come in through the layers of curtains, not to mention the bed draperies. The only modern item in the entire room should be a box of Bryant and May's matches. Half-empty bottles of 'medicinal' ether can be scattered around at your discretion. For some reason you will have problems with insomnia.
A painting of Rossetti's bedroom, which his assistant Treffry Dunn could find nothing good to say about.
With these helpful cues, it should be simple to decorate your home like Dante Gabriel Rossetti! Just be sure to save enough money for the therapy bills that are sure to ensue.