The same way you all need to wear your BOB occasionally to get used to the extra weight, you need to wear any armor also to get used to the weight, get some strength in the neck muscles where it mostly weighs in and find the places where it rubs bad on your body to line with some silk or at least fine material. Women will have a problem with the breasts if they do not have a bit of polstering near the nipple area and both men and women need to get some extra baby powder around the neck area and under your armpits against chafening of the tender skin there.
If you have armor with a collar, line the collar with soft materials also. The WWI/WWII did not wear a silk scarf because it was fashionable, the leather jackets neck collars dried from salty sweat wore the skin off of their necks from constantly scanning the skies for the enemy airplanes.