Hello! I would like to read as many sources as you guys can come up with. :D To clarify, I mean sources stating how padded armour should be made, how many layers, which materials, treatment of the materials... Thank you in advance!

Ordinances of Louis XI of France (1461-1483)
And first they must have for the said Jacks, 30, or at least 25 folds of cloth and a stag's skin; those of 30, with the stag's skin, being the best cloth that has been worn and rendered flexible, is best for this purpose, and these Jacks should be made in four quarters. The sleeves should be as strong as the body, with the exception of the leather, and the arm-hole of the sleeve must be large, which arm-hole should be placed near the collar, not on the bone of the shoulder, that it may be broad under the armpit and full under the arm, sufficiently ample and large on the sides below. The collar should be like the rest of the Jack, but not too high behind, to allow room for the sallet. This Jack should be laced in front, and under the opening must be a hanging piece [porte piece] of the same strength as the Jack itself. Thus the Jack will be secure and easy, provided that there be a doublet [pourpoint] without sleeves or collar, of two folds of cloth, that shall be only four fingers broad on the shoulder; to which doublet shall be attached the chausess. Thus shall the wearer float, as it were, within his jack and be at his ease; for never have been seen half a dozen men killed by stabs or arrow wounds in such Jacks, particularly if they be troops accustomed to fighting.

Dominic Mancini (1483): writing about the archers in Richard III's army
They do not wear any metal armour on their breast nor any other part of their body, except for the better sort who have breastplates and suits of armour. Indeed, the common soldiery have more comfortable doublets that reach down below the loins and are stuffed with tow or some other material. They say that the softer the garment the better do they withstand the blows of arrows and swords, and besides that in summer they are lighter and in the winter they are more serviceable than iron.

Howard Household Accounts (mid 1400s):
I took to the doublet maker, to make me a doublet of fence; for every four quarters: 18 folds thick of white fustian, and 4 folds of linen cloth, and a fold of black fustian to put without.

Regulations made by the Armourers of London. 15 Edward 11. A.D. 1322. Letter-Book E. fol. cxxxiii.
That an aketon and a gambeson covered with sendale, or with cloth of silk, shall be stuffed with new cotton cloth, and with cadaz, and with old sendales, and in no other manner. And that white aketons shall be stuffed with old woven cloth, and with cotton, and made of new woven cloth within and without.

Companion of Hernan Cortez (early 1500s)
The armour which they use in war are certain loose garments like doublets made of quilted cotton, a finger and a half thick, and sometimes two fingers; they are very strong. Over them they wear a doublet and hose all one garment, which are corded behind. This garment is made of thick cloth and is covered with a layer of feathers of different colours, making a fine effect… for neither arrows nor darts pierce them, but are thrown back without making any wound, and even with swords it is difficult to penetrate through them.

Aguado, History of Venezuela (mid 1500s)
Out of sacking or light linen cloths they make a kind of surcoat that they call 'escaupil'. These fall below the knee, and sometimes to the calf. They are all stuffed with cotton, to the thickness of three fingers. The layers of cotton are quilted between folds of linen and sewed with rough thread…

Awesome, thank you very much! Do you happen to know what is "cadaz"?

"Cadaz", also "caddis" - wool lint.
https://books.google.com/books?id=UGAJAAAAQAAJ&pg=PA167&lpg=PA167&dq=caddas+etymology&source=bl&ots=SctKAgmz8f&sig=Nt92BprU9nkDCQzq_Y6_zpp_lGw&hl=en&sa=X&ei=0HvbVIyBGsm6ggTqiIPAAw&ved=0CE0Q6AEwCQ#v=onepage&q=caddas%20etymology&f=false

Especially have a look at the Paris armourers guild rules on Manning's page. This Facebook thread discuss some elements of the translation not covered by Manning. Btw. I believe it is John Hewitt, Ancient Armour, p 239, who is to be praised for bringing this text to light.

Further, the Paris Armorer's Guild regulations also give instruction for the padded pavilion which goes beneath the aventail.