The operation of the scam is highly unpredictable and often misleading. But usually, the operation would centre on the usual statements and involve the same intricacies. At first, the investors are contacted, typically with an offer like "A rich person from the needy country needs to discreetly move money abroad, would it be possible to use your account?” The sums involved are usually in the millions of dollars, and the investor is promised a large percentage as reward.

The proposed deal is often presented as a harmless in order to put off participants from contacting the authorities at a later point of time. The operation is professionally organized in Nigeria, with offices, working fax numbers, and often contacts at government offices. The investor who attempts to research the background of the offer will usually find that all pieces fit perfectly together.If they then agree to the deal, the scammer will send several documents bearing official government stamps; seals etc., and then introduce delays, such as "in order to transmit the money, we need to bribe a bank official. Could you help us with a loan?" or "In order for you to be allowed to be a party to the transaction, you need to have holdings at a Nigerian bank of $100,000 or more" or similar of that kind.

Sometimes psychological pressure is added by claiming all the possible justifications. Sometimes, victims are invited to Nigeria and are asked to meet real or fake government officials. Some victims that travel are instead held for ransom. In some cases they are smuggled into the country without a visa and then threatened into giving up more money, as the penalties for being in Nigeria without a visa are especially severe. In the most extreme cases the victim is even murdered after he hands over the money or any other transactions.In any case, the promised money transfer never happens. What they actually claim does not exist. The country involved is not always Nigeria. Ghana, Côte d'Ivoire, South Africa and other West African states are sometimes seen. Occasionally the scam operates from a non-African country such as the Netherlands (Amsterdam), the United Kingdom (London), Spain (Madrid) or Canada (Toronto) but this tendency is on the rise.

A variant of the scam will appear to be sent by a barrister, representing the estate of some long-lost relative you never knew you had (your last name will be inserted into the email message) who perished along with his family in a car or airplane accident last April; the scammer will claim to have gone to a lot of trouble to find you in order to give you a share of the millions of dollars available if you'll just forward your bank account information to him.Another variant pretends to be a "winning notification" from a lottery company, typically in the UK or the Netherlands, requesting payment in advance to collect the sum that the victim has "won". In a newer version of the scam, the scammer offers to buy some expensive item (which the victim advertised on eBay, for example) by official, certified, bank or cashier's check. The check will have a mutually agreed higher value than the price of the item, so the scammer asks the victim to wire the extra money to some third party as soon as the check clears.

The check typically clears after one or two days, but the fact is the counterfeit is not detected until several days or weeks later, by which time the victim has sent the item and the "additional money" to the scammer and his representative. Most banks will hold the victim accountable for the value of the counterfeit check.The latest variant of the scam are the fake charity and fake church scams. In this type of scam the victim is asked to donate or invest in a local (often West African) charity or church. While no direct monetary benefit is presented to the victim, these scams are perpetrated by the same scammers that also employ more traditional advance fee fraud and the scams follow roughly the same modus operandi as the previously mentioned scams.

Interestingly, 419 spam is significantly less sophisticated in its delivery methods than almost all other spam regularly seen. The spam is almost always sent via free web mail services such as Hotmail or very occasionally with paid services, often paid for with credit card details stolen from former victims. This is also the method used to pay for the hosting of websites for the fake banks, companies and escrow services used in the later stages of the scam.The spams are normally sent from internet cafes, the addresses to be sent to and bodies of the mails copied and pasted from memory sticks into the web mail interface. Some London-based gangs have been known to use Spam ware on laptops which they secretly connect to the cafe's network, but even this software is notably out-of-date.

While this method is significantly more labor-intensive per mail sent than others, it offers near-total mystery and allows them to quickly relocate. The often very professional layout of web pages and so on used in the scams suggests that they do not lack technical sophistication at least at the upper levels of the gangs.