The Shulhan Aruch (O.H. 262:1-3), based on the Gemara (Shabbat 119a), writes that one should set one’s dining table, make the beds and prepare the home such that all will be ready when one returns from the synagogue on Friday night. Rabbi Pinhas Horovitz (Sefer Hamikna Kiddushin 41a), discusses the Gemara’s opinion (ibid) that preparing for Shabbat is actually a biblical Mitzvah, based on the verse (Shemot 16:5) “Vehechinu Et Asher Heviu”.
Interestingly, the Arizal (Sha’ar Hakavanot, pg. 72a) was particular about setting a table that had four legs since this was the type of table used in the Bet Hamikdash. Although one should not replicate the artifacts of the Bet Hamikdash, having a four-legged table is a symbolic reminder of the Shulhan that was used there, and not a replica.
The rush and stress to prepare for Shabbat can lend itself to conflict.The HIDA (Avodat Hakodesh) and the Ben Ish Hai (Parashat Vayera, Shana I, § 1) write that last few hours and minutes leading into Shabbat are especially prone to strife between husband and wife, or with one’s children or servants. Furthermore, Rabbi Haim Palagi (Sefer Kaf Hahaim 27:35) writes that a household which experiences strife right before Shabbat is at risk of experiencing something bad the following week. Therefore one should do all that is possible to prevent any conflict as Shabbat approaches.
Rabbi Shalom Messas (Shemesh Umagen, vol. IV, Orah Haim, § 15:1) writes that the Moroccan custom is that Mizmor LeDavid is recited sitting down since this is not when one accepts Shabbat. Furthermore, Lecha Dodi is also recited while sitting and only during the last stanza of “Bo’i Beshalom” does one stand up. In other Sephardic communities, Mizmor LeDavid is when one accepts Shabbat and thus it is recited standing up. The Ben Ish Hai (ibid:§ 2), based on the Arizal, writes that in the last stanza of Lecha Dodi, one should turn to the west and then turn to one’s right and then to one’s left when saying “Bo’i Kallah”. Rabbi Ovadia Yosef (Halichot Olam, vol. III), citing Rabbi Ya’akov Emden, says that one should bow when turning to one’s right and left. Nevertheless, the source of bowing by Boi Kallah is unclear and many simply turn to all directions.
Summary: One should prepare one’s home and oneself for Shabbat. One should be careful to avoid strife in Erev Shabbat. The Moroccan custom is to sit for Mizmor LeDavid and for Lecha Dodi, and to stand for the stanza of “Bo’i Kallah”.