Ideally, a nice Menorah should be used.
The Lubavitcher Rebbe discouraged the use of Menorahs with round branches as per Rashi’s interpretation. Instead, Chabad use either a Menorah with diagonal (or square-shaped) branches, or one with no branches at all.
The Menorah must be designed so that all the flames are in a straight line and at the same height. The flames should not be too close together, as they need to appear noticeably distinct. [Furthermore, wax candles need to be sufficiently spaced so that the heat of the flames do not melt the wax of the adjacent candles.] One should be especially attentive to this when improvising without a Menorah.
Each day of Chanukah, the Menorah is prepared in advance, so that it is ready at the appropriate time.
The Shamash is situated higher or separate than the other flames.
One Shamash is sufficient for multiple Menorahs when they are right next to each other, but not when they are situated in different parts of the room.
