method to print design with grids

[Klarissa]

This method requires Photoshop

When your design is open:
Select all
Copy design
open Photoshop
import a scanned copy of a grid, or draw one or download one from the internet.
Paste design onto a new layer underneath the grid.

[Puybaret]

Thanks for the tip... even if Photoshop license might be too much expensive for such a need. [;)]
Remember also that exporting to SVG then importing + adding a grid with Inkscape might give better results since the plan will be in vector graphics.

By the way, if you want the grid in the Sweet Home 3D itself, you could also use this older tip.