For kiddush and havdalah should you hold the cos in the palm of your hand? If so is it a chiyuv or just a praiseworthy thing to do? If it is uncomfortable for someone, can they not?
What is the reason for this?
According to Shulchan Aruch there is no obligation on how the cos has to be held. According to kabbalah, there is a preference to how it should be held. Some say that it should be held in one’s palm, which his fingers around it facing upward, (M:B 183-15 in the name of the Shela) others though (Eliyahu Rabba 183-7) say it should be on the fingers themselves. Aruch Hashulchan-5, and Shulchan Aruch Horav- 7 bring both opinions. Also see Kaf Hachayim 183-20.
If it is uncomfortable for you it is not an obligation.