Do you start off by creating a wireframe and then make iterations until you're happy and then develop code?
Solidify your idea by making sure that there is a market there. That means putting everything into a presentation, similarly to create a Product specific business plan. Speak with your tech team to decide upon technologies and commercial of the shelf software licenses, including hosting. Design a SIMPLE and good looking UI/UX and apply standard software methodologies such as SCRUM from development, Monitor progress and milestones. Most importantly target on "small" and doable product feature. One by one start adding. Place your product in the market and test-bed it fr FREE. Evolve and change features and functionalities.
Remember Marketing is NOT everything ... but it is!