1) The custom is to cover the eyes with the right hand while saying the first Posuk of "Shema Yisroel, Hashem Elokeinu, Hashem Echad".
The reason for this is to make certain that the person reciting it doesn’t gaze at anything else while saying this important Posuk, and thus may prevent his/her Kavanah (which is mandatory for this Posuk).
Some maintain that the eyes should remain covered until after "Baruch Shem K’vod Malchuso L’Olam VaEd" which according to some Poskim must also be said with Kavanah in order to satisfy your obligation (See Orach Chaim HaKadosh Parshas VaYeira. See Chayei Adam Klal 21:10. See Biur Halacha Siman 61:13). However, if by looking in the Siddur you will have better Kavanah it is best to do so.
2) A left handed person should also use his right hand to cover his eyes. (Orchos Rabeinu from the Steipler Gaon, Vol. 1 page 53. Also see Shu"t Be’er Moshe (Debrecin) Vol.2 Siman 1)
One who wears eyeglasses may place his/her hands over their glasses, and need not remove them. (Shu"t Az NidBiru Vol. 12 Siman 53).
Reader’s Question:
B’ezrat Hashem, this coming week, "V’Tein Tal U’matar" will begin in Eretz Ha’Muvtachat/Israel.(Editor’s note:In Chutz L’Aretz we begin saying it at Maariv of December 4th) What about a person VISITING Israel? Should he say it... and what should he do when he returns to the Galut?
My Answer:
A Ben Chutz l’Aretz, while visiting Eetz Yisrael is a Machlokes HaPoskim. Some say, as long as he plans to return to his home in Chutz L’Aretz within the year (or before the end of 60 days of the season of rain, according to some Poskim) he says what he would say at home. (Pri Chadash, Rav Shlomo Zalmen Auerbach Zatzal and others).
Others say that he says as the people in Eretz Yisroel are saying (Mishna Berura seems to pasken like this, Bais Baruch and others). A Rav should be consulted as to which opinion to follow.
When he returns home to Chutz L’Aretz he resumes saying what everyone else in Chutz L’Aretz is saying, according to all opinions.
Our holy sages, the Chazal tell us תנא דבי אליהו כל השונה הלכות בכל יום מובטח לו שהוא בן עולם הבא, שנאמר הליכות עולם לו, אל תקרי הליכות אלא הלכות - one who studies [at least two] Halachos daily is assured a portion in Olam Haba - the world to come. (:מגילה כ"ח )