The process of reproducing period uniforms and civilian garments always starts from a thorough research, into both primary and secondary sources, period and modern ones.
I already own a vast library of books, magazines and PC files on uniforms and costumes, but whenever possible an archival research is also done (as for the Maison du Roy exhibition).
When all relevant infos are collected and organised, a search is done for the correct materials. I only use fabrics, trimmings, buttons, etc. that are exactly matching - or as close as possible - to the original ones, comparing them to original samples and the extant garments to be replicated, or other very similar ones.
When I can not use one of my many already well tested out patterns, a new one is developed, based on the original garment (when possible) and all other infos that have been collected.
Once the garment is cut (with as little fabric waste as possible, as good tailors are used to do!), it is basted for a preliminary fitting on the stand, so as to check that it hangs well, that shape and proportions are correct, and also that the style and flavour of the period is nicely and elegantly captured. Another fitting may also be done on the customer, whenever this is feasible.
Then the actual labour of sewing is done, what can take many hours or even days on end, and is carried out strictly following period tailoring practice and techniques, almost entirely by hand. The final product offered reflects in its top-range quality this painstakingly laborious and carefully executed work.
You really cannot find anything better anywhere for this price!