Identify the competition in the marketplace. Know that there is room for more than one (or two or three) Home Design Magazines in each and every market.
Research the ad market.
Design a business plan where you are profitable from the first issue. Never plan to ramp up, sometimes your first issue is your best.
Determine your frequency. Most popular are 4, 6, or12 times a year.
Hire a dedicated home design editor. Create a strong editorial calendar with advertising hooks for each issue and consider seasonal trends (home décor, outdoor entertainment, gardening) and other popular features such as before and after renovations, Top 10 Best Kitchen redesigns, The Garden Issue, The Holiday Issue, profiles of rising star designers, Meet the Builder sponsored content, etc.)
An event linked with each issue also helps, particularly when you can reach your readers through a city/regional party or to host a B2B event where local builders, designers and architects meet/greet. These are also likely your current and prospective advertisers.
While you might start with your existing B2C sales team move to dedicated home design sales team as soon as possible and expect to do more face-to-face sales calls.
Involve key stakeholder groups early.
Partner with local business organizations and associations to build audience.
Add other revenue streams such as: events, email notifications, e-newsletter, website, custom publications, content marketing, podcasts. Also consider an awards completion for the design community in your area.
