PCB
Hi,
You must have a "BOM" = component listing with all relevant data for the ordering of pieces/Components, as (ev. preferred)producer/Type Nr,versions codes, event. Distributors/sources who you prefers...
Than tolerances/power/Work-Voltages/size(SMD)...
All data for absolutly clear determinating a component!
For populating from a firm (f he will make it automated) you need a mask film/data-file (schablone for solder paste printing) and a file with Pick-Up points/data-file (or you have their on your components/library) as i.e. glue points too if an SMD PCB is both side populated (in the library to deliver from you as best...)...
Of course a montage schema/populations drowing with all your ref-des on right place & as best the values from your components too.
To end eventuell some specifical montage instrucions... These is relative easy
If it will manuell populated, some simpler is your process/less documents are needed, but more time too for tho working personal: usual is than more expensive...
Regularly is better to say to a firm; "(as general undertaking/firm), buy for me components, order the PCB from your partner/vendor & populate/event. test too the card; you have some easyer/quality is better and so on...
K.