The Islamic State (Isis) released an English language manual advising western would-be terrorists to wear crosses and aftershave when plotting attacks, so as to go undetected. An Australian Jabhat Al-Nusra fighter tweeted a link to the guide under the Twitter handle @AhmedShaheed11 in October.

He wrote: "Much needed piece of work for the new and often reckless generation of jihadis." The Twitter account has since then been locked.

The 58-page document titled 'Safety and Security Guidelines for Lone Wolf Mujahideen' was published online and highlights various recommendations from trimming beards to wearing watches on the left hand rather than the right in order to go unnoticed and plot below the radar attacks.

"If you can avoid having a beard, wearing qamis (Islamic tunics), using miswak (teeth cleaning twigs) and having a booklet of dhikr (prayers and devotional acts) with you, it's better. It is permissible for you to wear a necklace showing a Christian cross," it explains.

"As you know, Christians - or even atheist westerners with Christian background - wear crosses on their necklaces. But don't wear a cross necklace if you have a Muslim name on your passport, as that may look strange," the Daesh guide adds.

Along with dressing tips, the manual also suggests safe places to hold meetings. "A nightclub, because of the loud music, the drunk people and the crowd, could actually be a good location to secretly discuss the details of an operation," the author advises.

According to Memri Cyber and Jihad Lab, the manual is divided into 12 chapters which touch on a range of subjects from online security encryption and safe-house recommendations to suggestions for conferences and meetings along with transport and weapons security.