1-Figure out where you think you can or will be able sell your prints? (eBay, Galleries, Cafes, Agents, ...)
2-Go try a sell some real product (made from your35mm negs) in that market?
3-Did it work? Can you make money at what that market will pay? Why/Why not?
4-Solve the problems you find.
5-Start again at 1 or 2 as appropriate.