Muwatta Imam Malik Book of Hajj, Hadith 199

Yahya related to me from Malik that he had heard that when Salim ibn Abdullah intended to go into ihram he would call for some scissors and trim his moustache and beard before setting off and before going into ihram.

وَحَدَّثَنِي عَنْ مَالِكٍ، أَنَّهُ بَلَغَهُ أَنَّ سَالِمَ بْنَ عَبْدِ اللَّهِ، كَانَ إِذَا أَرَادَ أَنْ يُحْرِمَ دَعَا بِالْجَلَمَيْنِ فَقَصَّ شَارِبَهُ وَأَخَذَ مِنْ لِحْيَتِهِ قَبْلَ أَنْ يَرْكَبَ وَقَبْلَ أَنْ يُهِلَّ مُحْرِمًا .