PCB Design is the process which convert the schematic to Gerber, the PCB factory can fabricate the PCB with the Gerber and relevant requirments.
There including many PCB Design softwares on marktet, such as Candance, Mentor Graphis, Altium Designer, Eagle etc.
For PCB Design, we based on the final schematic with PDF or ".sch" format, and below is the layout prepare list for quotation,.
1) Finalized schematics (.sch format will be better);---Attached Templates for reference.
2) Components' datasheets (eg: ICs and specific connectors, resistor and capacitor must mention size. If can provide Labrary, that will be better);---Attached Templates for reference.
3) Figure and instructions for key component placement (DXF document if you have);---Attached Templates for reference.
4) PCB layer definition(If possible for multilayer PCB);
5) List of specific requirments (such as high frequency, impedance, trace length/width);
6) Finalized BOM, if can provide.---Attached Templates for reference.