1. Ḥanuka candles are kindled in the evening, each of the eight days of Ḥanuka. The custom of many communities is to light the candles at sunset, which is approximately at 4.30 p.m. in NYC. Other communities light the candles at nightfall (approximately 5.00 PM). In either case, the candles must contain enough fuel at the time of the lighting to burn for 30 minutes after nightfall. If one did not light the candles early in the evening, they can be kindled later, when the family is home.
2. The candles could be made of wax, paraffin, etc., but ideally one should use olive oil, because the miracle of Ḥanuka happened with olive oil. In addition, oil candles will last for more time than small wax candles. The Miṣva of Ḥanuka candles cannot be performed with 'electrical candles', even when real candles are not available. An electrical Ḥanukia, however, can be placed in the house in addition to the regular Ḥanukia, especially during day-time.
3. Some families have the tradition to place the Ḥanukia outside the door, on the opposite side of the Mezuza, which technically, is the best place for it. Nowadays, however, most families place the Ḥanuka candles inside the house, close to a window, in a spot that is visible from outside.
4. Technically, it is enough to light one single candle every night. As we say in the Berakha: lehadlik NER Ḥanuka (to light the candle, not candles, of Ḥanuka). As we all know, the traditional custom is to add one more candle for each night. However, in extreme cases where one cannot light additional candles, for example, if one is on a trip or in a Hotel room, etc., lighting one candle any night will be enough.
Ḥanuka begins Saturday, December 8th, 2012, after Shabbat is over.