For big product launches, design is absolutely imperative to have done well. Hopefully, where you are working, you have a product management team, product owner, or marketing team that knows exactly how the product, system, or website needs to look like and they have a pretty darn solid way of showing it: wireframes, or design specs, etc.
Hopefully, even, they may have these design requirements all spec’d out even before you begin looking at it or creating stories! But often, they don’t. So how does design fit into Scrum when developers are demanding to have wireframes and sometimes, even, the whole daggum thing designed-out before they can begin work (I think this can be unrealistic).
I like to start with an “Iteration Zero (0),” a design iteration that takes into account time to wireframe, speak with stakeholders and involve a development lead to give some insight into how the system architecture may or may not be able to handle some of the design requirements.
The developer must be able to take something from the design meetings and the design specs/wireframes/design requirements must be just good enough for the developers to start work on. This has to be a healthy balance between what is needed by the developers and what can be fleshed out by the product owner and designers.
With my current client, we’ve found that if we take a test driven development approach (building out test cases and use cases) we can easily fill in the design aspects as we create modules or stacks of the whole. Woah there, it’s looking iterative and agile! So what we have here is a piecemeal development process that starts with the conversation with the product owner and designers (who also build test cases), and chunk out the whole development into design stacks that can be consumed by development.
Bottom line? Design needs to be just as iterative as any other agile process. There needs to be frequent inspection and adaption of the system as it’s built out. For a more detailed look at this check out this link here: [Agile Design].