Sephardic weddings are not always in a shul. When they are, the Choson and Kallah face the Aron, instead of turning their back to the Aron. Otherwise, as was mentioned by “i love coffe”, they face the tzibbur.
Regarding the “Avram Siz” – I’ve never heard of that. It’s called a “Shabbat Hatan” and is the week after the wedding (unless the couple is not too frum and runs away on a “honeymoon”, then it’s the week before). After the Choson’s aliyah, they read a few P’sukim from Parshas Chaye Sarah “Ve’Avraham Za’ken”, where Avraham makes Eliezer swear to not bring back a Canaanite girl for Yitzchok. This is read by 2 separate people, one with the parsha and one with targum. After davening, they have a “sebet” (Shabbat in Arabic?), which can often be a large [second wedding] – full meal with family and sometimes many guests.