What is the advice for a friend who goes out naked into the street at noon?

It is permissible to advise a friend to fear Allah and to wear clothes to cover the 'awrah and adorn oneself with them, for it is a blessing from Allah, as stated in His verse: (O Children of Adam! We have bestowed upon you raiment to cover your shame, and as an adornment; and the raiment of righteousness, that is better). Clothing is of two types: essential for covering the 'awrah, and aesthetic for adornment. One must thank Allah for these blessings and acquire piety, which is the best provision. Piety means obeying Allah's commands and avoiding His prohibitions, among which is covering the 'awrah. One must advise with wisdom and good counsel, as stated in His verse: (Invite to the Way of your Lord with wisdom and good instruction).