Background: I am working with a client that is not ready to let go of their archaic website. We are designing a new feature that will be hosted on separate domain under their branding with the intention of integrating the two sites in the future. The client wants the two sites to be as seamless as possible.
Of course, this is tricky because building a separate extension of their site is going to require updated design principles and technologies. Additionally, linking between both sites is a whole challenge in itself (where to link, how not to lose users between both sites). Any tips from you savvy UX designers out there?