Wearing shoes of deceased:
One is not to wear the shoes of a deceased person due to fear of danger. It is not to be given even to a poor person. It may however be sold to a gentile who is purchasing it for personal use, and one may then give the money to a pauper as charity. [If one does not plan to sell/give them to a gentile to wear, they are to be torn and discarded. Some Poskim rule the above only applies towards the shoes that were worn by the deceased at the time of his/her passing. Other Poskim rule it applies to all shoes that were worn by the deceased throughout his illness, but not towards shoes that were worn prior. Other Poskim rule that if one knows the deceased passed away from a non-contagious disease, it is permitted to be worn in all cases. Other Poskim rule that the entire prohibition refers to shoes made from the leather of an animal who died on its own, and not to shoes of a dead person of which there is no restriction to wear.
Rainboots: One is not to wear rainboots of the deceased just as one does not wear his shoes.
Socks: There is no source for restricting the wearing of the socks of the deceased.
Other clothing: There is no restriction against wearing other clothing of the deceased.
 Sefer Chassidim 454; Keser Shem Tov 683; Kaf Hachaim 116/141; Nitei Gavriel 132/5
 The reason: As the shoes contain the sweat of his feat. [Keser Shem Tov ibid] And thus possibly contain a contagious disease. [Igros Moshe 3/133] See Brachos 57b “If one has a dream that the deceased has come to take his objects, it is a good omen, with exception to his shoes” [Koreis Bris 137a]; See also Gittin 68b that Ashmadaiy told Beniyahu Ben Yehoyada “He is making shoes for seven years and he wont even live for seven days” This implies that the shoes are not even worn by his son, as otherwise it would be inherited and Ashmadaiy would have no claim. [Makor Chesed on Sefer Chassidim ibid]
 Keser Shem Tov ibid; However see Atzei Levanon 46 that doing so is Baal Tashchis
 Atzei Levanon 46 that even those who are stringent, should only be stringent in this case; See Makor Chesed on Sefer Chassidim ibid
 Mishmeres Shalom Samech 11
 Igros Moshe 3/133
 Atzei Levanon 46; Atzmos Yosef, brought in Mishmeres Shalom Samech 11; Beis David 31; Gesher Hachaim in name of Rav Pesach Frank; brought in Igros Moshe 3/133 [but negated]; See Makor Chesed on Sefer Chassidim ibid
 The reason: As perhaps the animal was bitten by a snake, and the venom is absorbed in its skin. [ibid; See Chulin 94a]
 Mishmeres Shalom Samech 11; Nitei Gavriel 132/8
 Koreis Habris 51, brought in Nitei Gavriel 132 footnote 6