There is a range of Hexon grids to help you plan your battlefield layout, available free from the Kallistra website.
There are now nine free layouts:
3x4ft, 6x4ft, 4x8ft, 6x6ft, 5x10ft, 6x12ft, and a 113 hex layout (suitable for games such as Memoir '44, Commands & Colours, and others).
After downloading and printing your Hexon grid, the position of roads, rivers, terrain features, and fortifications can be sketched on the Hexon grid, making it easier for you to visualize your layout.
To download the full-range of hex grids, visit the website.