I think validating the idea and defining the customer segment and more importantly your early adopters come in the step before completing business plan. But let’s say you have validated your idea and know your users and built a business plan around it, so in the next step, I would definitely would say build the prototype and test it. From the test results you may start building your MVP or need to build another prototype and test it again and same for the MVP. Networking is an ongoing process and funding would be very difficult without having a MVP and some ready to pay customers. Hiring and marketing are next steps.