Like a new pair of shoes, new armor has to be "broken in". That means that it takes a while before it is really comfortable, regardless of the intensity of your training.
You should make sure that the shoulder lobes are always bent toward the front and not towards the back so that they protect your front side and no gaps develop between the Tsuki Tare and the Men lobes due to improper bending.
After training, the leather on the palm of the Kote should be smoothed out; don't dry them directly in the sun or on a heating unit, because otherwise the high quality leather will become brittle.
The Tare is tied to the Do after training so that the sweat of the inner-side faces outward and can dry. The better you care for the armor, the longer it will last!