The Gemara in Masechet Pesachim (100) discusses the requirement that one come to the Shabbat meal on Friday night with an appetite, so that he eats the Shabbat meal heartily.
To this end, Halacha imposes certain restrictions regarding one's eating on Erev Shabbat. According to the Shulchan Aruch, it is permissible to eat a normal-sized meal, the kind of meal one normally eats during the week, anytime on Erev Shabbat, provided that it will not satiate him to the point that he will have no appetite when Shabbat begins. One may not, however, eat a particularly large, festive meal on Erev Shabbat, unless it involves a Mitzva that applies specifically that day. For example, if a circumcision or Pidyon Ha'ben took place on Erev Shabbat, one may conduct a large, festive meal in honor of the event. Likewise, if one completes a Masechet (Tractate) of Talmud on Erev Shabbat, he may hold a large "Siyum" celebration. Large meals to celebrate an engagement, however, are forbidden, since modern-day "engagements" are not Halachically binding, and the meal is therefore not considered a formal Se'udat Mitzva (meal involving a Mitzva). The Mishna Berura (commentary to the Shulchan Aruch by Rabbi Yisrael Meir Kagan, Lithuania, 1835-1933) rules that one may host an engagement celebration consisting of light food on Erev Shabbat.
It should be noted that the Shulchan Aruch records a custom among some to refrain from eating even normal-sized meals within three Halachic hours before sundown on Friday afternoon.
Furthermore, the Mishna Berura mentions that one should avoid drinking alcoholic beverages close to Shabbat, as he may become inebriated and thus be unable to conduct the Shabbat meal properly.
In general, one must be aware of his eating patterns, and ensure that he eats on Friday in such a manner that he goes into Shabbat with an appetite.
Summary: Halacha requires that one sit down to the Shabbat meal on Friday night with an appetite. Therefore, it is forbidden to eat a large, festive meal – larger than a meal one normally eats – on Erev Shabbat, except as part of a Mitzva celebration that occurred on that day, such as a Berit Mila, Pidyon Ha'ben, or completion of a Masechet. Some have the practice to refrain from even normal-sized meals within three Halachic hours of sunset on Erev Shabbat. One must avoid drinking alcoholic beverages late on Friday afternoon.
