If you create your circuit board layout with KiCad, please observe the following tips.
We are happy to take care of generating the production data (Gerber export) for you. You just have to send us your .kicad_pcb file along with your order. All further steps are taken care of by our CAM engineers.
If the uncomplicated Gerber (and drill file) export in KiCad is carried out by yourself, you can check your finished production data directly in the integrated Gerber viewer. This helps avoiding queries.