When concept sketching, it's important to incorporate all of your ideas and opportunities from your SWOT analysis. Maybe you will combine the ideas that you have researched from existing products into one amazing solution...but push yourself to keep thinking of other ideas. Develop 3 - 5 sketches and include the following information depending on your product:
(building 3D sketches)
(with construction lines)
(annotation - what, how and why)
Ensuring that your concept sketching and foam core prototypes are set up for scale is important. Watch this clip to understand what can happen if your client doesn't understand scale...