How to make production in China?

I came up with an inexpensive and very necessary (albeit niche) device - a variation on the USB keyboard theme.
I have a three-dimensional model built in AutoCAD, renders and a description of what I want to get. Things are easy - to turn the model into a thousand ready-made devices in beautiful boxes.

If you were in any way related to the outsourced production of equipment in China, please share your experience. I am interested in all stages, ranging from finding a factory (there are thousands of them on alibaba.com ) to obtaining certificates and delivery.

Thank you in advance. I believe that it is not necessary to be Artemy L. to release the device of your dreams.
')
UPD: Target audience - not IT specialists. Do not wait yet another happy hacking keyboard.