If there may be any question about the Jewish lineage of a bride-to-be or bridegroom, his or her female antecedents should be confirmed as having been Jewish (born of a Jewess OR halachically converted) back to when a shomeret Shabbat woman has been positively identified (or back as far as possible). As a practical matter, three or four generations may be as far back as most Jews can be traced.
 
Also, make sure that if there was any divorce, that the divorce was kosher, with a get.

We are required to eat two meals on Jewish festivals, each preceded by kiddush, one in the evening and one in the morning. For both meals for each Jewish festival day (and all three meals on Shabbat), say ha'motzi over two complete loaves of bread, each of which is at least 1.3 fl. oz. in volume. 

Source of Saying Jewish Festival Kiddush
Some kiddushes are commanded by the Torah (d'oraita); the others are from Chazal (d'rabanan), as follows:
Kiddush d'Oraita

• First night of Jewish festivals
• Night of seventh day of Passover
• Night of Shmini Atzeret.

Kiddush d'Rabanan

• First day of Jewish festival
• Second night of Jewish festival
• Second day of Jewish festival
• Seventh day of Passover
• Eighth night of Passover
• Eighth day of Passover
• Shmini Atzeret day
• Night and day of Simchat Torah.

Source of Jewish Festival Kiddush Location
Saying Jewish festival kiddush at the place where you will eat your meal is a rabbinical (d'rabanan) enactment.
Jewish Festival Kiddush-Meal Quantities: Evening

• For evening kiddush for a first-night (d'oraita) Jewish festival, a minimum of 4 fl. oz. (119 ml) of wine must be blessed on and at least half must be drunk.
• For evening kiddush for a second-night (d'rabanan) Jewish festival, a minimum of 3.3 fl. oz. (99 ml) of wine must be blessed on and at least 2.0 fl. oz. must be drunk.
• For the evening meal, as on the first two Shabbat meals and for all required Jewish festival meals, a minimum of 1.9 fl. oz. (56 ml) of bread must be eaten within four minutes.

Eating Requirements for Jewish Festival Morning Kiddush
There are two separate eating requirements during the daytime. They may be combined (say/hear kiddush and start the main meal right away) but are often done separately (say/hear kiddush and then eat some light foods and beverages; the main meal is eaten later in the day).
Note Since eating and drinking requirements on all morning kiddushes (both Shabbat and Jewish festivals) are d'rabanan, the required beverage amount for morning kiddush is only 3.3 fl. oz. (99 ml) instead of the d'oraita 4 fl. oz. (119 ml) (which is required for kiddushes for Shabbat evening and all first-night Jewish festivals).

• Morning kiddush requires a halachically legal “meal” with these elements:
  • Blessing on a minimum of 3.3 fl. oz. (99 ml) of wine (or other beverage),
  • Someone's drinking at least half the beverage, followed by
  • Eating at least 1.3 fl. oz. (39 ml, or 1/6 cup) of some type of mezonot within four minutes. 
    Note If you drink at least 3.3 fl. oz. (99 ml) of wine within 30 seconds, you do not need to eat mezonot.
    Note You do not need to drink the wine or other kiddush beverage to fulfill “establishing a meal.” You may hear kiddush and then simply eat the required amount of bread or mezonot. This applies to Shabbat or Jewish festivals, evening or morning.
     

 

• The real meal (kovei'a se'uda) requires eating at least 1.9 fl. oz. (56 ml) of bread (or matza during Passover!) within four minutes. It must include enough food to satiate. 
  Note You can simultaneously fulfill the requirement to “establish a meal” and to “eat a meal” by eating one (the same) piece of bread.

Place the bread back onto the table before saying birkat ha'mazon if the bread had been removed during the meal. This is a non-binding custom, not a halacha.

If insects such as bees or non-diseased mosquitoes don't carry diseases but they bite or sting you, you may kill them on Jewish festivals, as well as trapping them or chasing them away with bug spray. Unlike on Shabbat, on a Jewish festival you may kill insects that are a nuisance, such as gnats or flies. These halachalot apply to all Jewish festivals unless they fall on Shabbat (or are Yom Kippur).

You may brush your hair on a Jewish festival, but only if the brush bristles bend easily. You may not use stiff bristles or combs since they might pull out some hair. 

You make take medicines for any reason on d'rabanan Jewish festivals--even medicines not allowed on the first day of Jewish festivals--except:

• Medicines that you smear on skin.
• If the Jewish festival falls on Shabbat (which can only be second day of Shavuot).
  Note The d'rabanan Jewish festivals are the second day of Jewish festivals except Rosh Hashana (actually, the second day of Rosh Hashana IS d'rabanan but has the status of d'oraita), plus the last day of Passover and Sukkot outside of Eretz Yisrael.

You may not DRINK or DERIVE ANY BENEFIT FROM open (unsealed), non-mevushal (uncooked, previously kosher) wine or grape juice that has been handled by:

• A non-Jew, or
• Any Jew who intentionally does not observe the laws of Shabbat.

In addition to prayer obligations (see Women: Minimal Prayer), women and girls 12 years old and up are required to keep these time-dependent positive commandments, among others:

• Candle-lighting for Chanuka (see Chanuka: Candles: Who Should Light )
• Candle-lighting for Shabbat, Jewish festivals, Rosh Hashana, and Yom Kippur.
• Havdala (say or hear) after Shabbat, Jewish festivals, Rosh Hashana, and Yom Kippur.
• Kiddush (say or hear) on the first night (or first two nights outside Eretz Yisrael) of every Jewish festival, and also the next morning.
• Passover (all commandments, including eating matza at the Passover seder).
  Note Because she must eat matza, she must therefore say birkat ha'mazon afterward (so if a woman omits ya'ale v'yavo in birkat ha'mazon at the seder, she must repeat birkat ha'mazon!).
• Megila on Purim.
• Shabbat (For why women must keep time-dependent, positive commandments on Shabbat, see Introduction to Shabbat )
• Shofar on Rosh Hashana.
  Note Jewish women universally accepted upon themselves to hear shofar on Rosh Hashana, but they only need to hear 30 blasts.
• Hearing the reading of Parashat Zachor.

For food that is not fully cooked, you may not remove and replace the lid (such as when checking to see if the food is cooked).
Reason Replacing the lid helps cook the food (the food's being fully cooked before Shabbat avoids this problem).
When using a crockpot or slow cooker with a glass lid, however, the food does not need to be fully cooked.
Reason You can see how well cooked the food is through the lid.
 

Owning a business that has any violations of Torah laws is forbidden.

You do not need to stand up for old people (as a form of honoring them) unless the old person is over 70 years old and is shomer mitzvot. This applies to women, too, if they are 70 years old or more and are shomrot Shabbat.
 

If you must eat a meal including at least 1.3 fl. oz. (39 ml, or 1/6 cup) of bread on Yom Kippur, say birkat ha'mazon afterward. Add ya'aleh v'yavo (and if Yom Kippur coincides with Shabbat, also add retzei).

You may continue riding in a car or taxi driven by a non-Jew between sunset and dark (tzeit ha'kochavim) beginning a Jewish festival, even if the vehicle is driven just for you. You:

• May not do this on Shabbat.
• Must have already paid before sunset. 
• May not open a door that will cause a light to turn on or do any other melachot.
• If you have already traveled outside techum, you may move only 4 amot (85” or 116 cm) away from the vehicle, unless the driver leaves you off in an enclosed domain (any area surrounded by walls or an eruv), in which case you may go anywhere in that domain.
• If you had not gone outside of techum, you may go anywhere in the domain and you may also go up to 2000 amot (3,542 ft. or 1,080 m) outside of the domain.

1 Tefach = 4 fingers' width = 3 ½” (8 cm) to 4" (10 cm)
Lavud = 3 Tefachim = 10 ½” (27 cm) to 12” (30 cm)
1 Ama = 6 Tefachim = 21 ¼” (54 cm) to 24 1/2” (63 cm) (depending on the application)
10 Tefachim = 40” (1 m) (for Shabbat border)
 

Tachanun is related to judgment. Tachanun is NOT said at times of din/judgment:

• At night,
• On Tish'a B'Av,
• In a house of mourning, and
• Yom Kippur.

Tachanun is also NOT said at times of simcha/happiness:

• Shabbat,
• Jewish festivals,
• Rosh Hashana, and
• Rosh Chodesh.

• Isru chag (the day after each of the Jewish festivals),
• Entire month of Nisan.

• All of Chanuka, Purim, Shushan Purim, Tu B'Shvat, Rosh Chodesh, and from Rosh Chodesh Sivan until the day after Shavuot.
• Tishrei from shacharit before Yom Kippur until after Simchat Torah (Shmini Atzeret in Eretz Yisrael). Resume saying tachanun:
  • Second day of Cheshvan, or
  • Day after isru chag of Simchat Torah (this is the more prevalent custom among Ashkenazim). Each person should follow his or her family or community custom.

• Mohel,
• Sandak, or
• Father of a boy having his circumcision.