The Prophet ﷺ said, "When the first ten days [of Dhul-Hijjah] begin and one of you intends to offer a sacrifice, let him not touch any of his hair or skin."
حدثنا سفيان بن عيينة عن عبد الرحمن بن حميد سمع سعيد بن المسيب
عن النبي ﷺ إذا دخلت العشر فأراد رجل أن يضحي فلا يمس من شعره ولا من بشره
Its isnad is sahih. Abdul-Rahman bin Humayd is the Qurashi, Zuhri, and he is trustworthy, his hadith is found in the collections of the group. The hadith was narrated by Muslim 3/1565, Abu Dawud 3/94 no. 2791, Tirmidhi 4/102 no. 1523, who said, hasan sahih, Nasai 7/212 no. 4362, Ibn Majah 2/1052 no. 3149, Darimi 2/104 no. 1948, and Humaydi 1/140 no. 293.