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[Various] Practices of Wearing ציצית and it's Rewards and Punishments. Containing 6 Se'ifim:
If a person does not wear a garment with four corners then he is not obligated in [the מצוה of] ציצית. [However,] it is good and proper that a person should be cautious to wear a small טלית every day, in order that he should remember the מצות at every moment. Therefore, there are five knots [in each corner] which correspond to the five books of the Torah, and there are four corners, so that in whichever direction he faces, he will remember. It is proper to wear ציצית over his garments and at the very least, he should be careful to wear ציצית at the time of prayer.

Great is the reward for the mitzvah of tefillin, and anyone who does not wear them is included in the group of "sinners of Israel" [sinning in their] bodies.

It is a Mitzvah to have them [tefillin] on all day, but because they [tefillin] need a clean body [meaning that] he does not pass gas, and [further require] that one not distract his mind from them, and not every person is able to be careful with them, the practice is not to wear them all day. Nevertheless every man needs to be careful with them that they should be on him during the reciting of Shema and Tefilah [aka Shemoneh Esreh].

The time to put them [Tefillin] in the morning is at the time when one can see his close friend from four cubits away and recognize him.

One is prohibited to put Tefillin on at night since he may forget [that he has them on] and sleep in them. If he puts them on before the sun sets and it happens to get dark, even if he wears them the whole night, it is permitted. [However] we do not teach [people] to do this. If he did not remove the Tefillin once the sun set since he had no place to guard them and therefore, left them on to protect them... This is allowed and is such taught.

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The Time of ציצית. Containing 3 Se'ifim:
Night is not the time of tsitsit, because [the obligation is] limited by [the verse] "and you shall see it" (Numbers 15:39). According to the Rambam, anything that is worn at night is exempt, even if it is designated for daytime use, and that which is worn in the day is required [to have ציצית], even if it is designated for nighttime use. And according to the Rosh, a garment which is designated for nighttime is exempt, even if it is worn in the day, and a garment designated for daytime, or both day and nighttime, is required [to have ציצית] even if it is worn at night. Rem"a: And a doubt regarding blessings is ruled leniently - therefore one shouldn't make a blessing on it unless it is worn in the daytime and it is designated for daytime (Hagahot Maimoni). And after the evening prayers, even if it is still day, one shouldn't say the blessing on it (Piskei Mahar"i, 121). And on the night of Yom Kippur one should put on the garment while it is still day and say the blessing on it (Tashbetz).

It is permitted to enter a bathroom with ציצית. Rem"a: And certainly to sleep in them is permitted. And there are those that write that it is our custom to not sleep in a טלית that has ציצית on it, also one shouldn't give it to a non-Jewish cleaner to clean. And all these things are so that commandments shouldn't become disgraced because of it. However, the custom is to be lenient [with regards] to sleeping in them (Kol Bo).

To not sleep - And in the writings of the Arizal it is written based on the mystical teaching [Kabbalah] that one should sleep at night while wearing a Tallit Kattan.

The Gemara relates that a heretic saw that Rava was immersed in studying halakha, and his fingers were beneath his leg and he was squeezing them, and his fingers were spurting blood. Rava did not notice that he was bleeding because he was engrossed in study. The heretic said to Rava: You impulsive nation, who accorded precedence to your mouths over your ears. You still bear your impulsiveness, as you act without thinking. You should listen first. Then, if you are capable of fulfilling the commands, accept them. And if not, do not accept them. He said to him: About us,

who proceed wholeheartedly and with integrity, it is written: “The integrity of the upright will guide them” (Proverbs 11:3), whereas about those people who walk in deceit, it is written at the end of the same verse: “And the perverseness of the faithless will destroy them.”