Answered by Sayyidi Habib Umar bin Hafiz (may Allah protect him and benefit us by him)
Recite Ayat al-Kursi, Surat al-Ikhlas, Surat al-Falaq and Surat al-Nas, (a minimum of 11 times along with these verses, also 11 times each)
قَالَ مُوسَى مَا جِئْتُم بِهِ السِّحْرُ إِنَّ اللَّهَ سَيُبْطِلُهُ إِنَّ اللَّهَ لاَ يُصْلِحُ عَمَلَ الْمُفْسِدِينَ
(Yunus, 10:81)
فَوَقَعَ الْحَقُّ وَبَطَلَ مَا كَانُواْ يَعْمَلُونَ
(Al-A`raf, 7:118)
وَإِن يَكَادُ الَّذِينَ كَفَرُوا لَيُزْلِقُونَكَ بِأَبْصَارِهِمْ لَمَّا سَمِعُوا الذِّكْرَ
(al-Qalam, 68:51)
Also read: Wird al-Sakran, Wird al-Nawawi and Wird al-Shaykh Abu Bakr bin Salim.