I've designed this initial layer test print to check the first layer's quality while calibrating my z-height, minimizing filament use. Both models are set to a height of 0.2mm. You can modify the height or scale in your slicer software to make the dimensions larger or increase thickness.

Additionally, you can employ multiple squares to assess various sections of the print bed in one go. I typically use a 100x100mm square to adjust the z-height or layer height during the printing process.

40x40mm: .5g 100x100mm: 2.5g