First of all, wear socks in wooden shoes. This is the most important tip we can give when wearing wooden shoes.
Although clogs are warm in winter (and fresh in summer). In the early days people would put hay in wintertime in the clogs for extra warmth.
For some people it can take some time before wearing wooden shoes are comfortable so please be patient. When you have problems at the instep place a little piece of foam to the inside of the wooden shoe.