Analysts Kantar predict UK shoppers will spend on average £246 ($327) each during the big event this year, with those in the US splashing out a marginally more restrained $298.

As always, tech hardware bargains are proving popular on Amazon with the retail giant naming the Nintendo Switch, a combi-drill from Bosch and of course its own Fire TV Stick among its most popular items so far.

John Lewis said it was averaging 19 sales per minute of a smart speaker by Sonos during Black Friday morning.

Here's a quick guide to making the most of the sale extravaganza.

1 Don't be dazzled by deals

Before you buy, it is always worth checking if the same product is cheaper somewhere else, and if so, finding out whether firms will price-match.

Some specialist sites can tell you if the product has been discounted more heavily before.

For example, Camelcamelcamel.com shows the price history of Amazon products - allowing shoppers to see if they have been offered more cheaply in the past.

Also bear in mind that just because a store claims to have huge discounts, it might not be the case, warns MoneySavingExpert.

"Some retailers may bill their sales as "up to 70% off" and only have one or two items at the highest amount off," warns the website's Jordon Cox in a blog post.

"What's more, just because an item says it has £100 off, for instance, it doesn't mean it's a steal. It could've been a ridiculously high price to start with and cheaper at a rival - which is why it's important to do your price comparisons beforehand."

2. Remember delivery costs

"Look at a company's delivery costs in advance to make sure you don't get a nasty surprise at the checkout," advises consumer watchdog Which?

"Some retailers offer a buy online and pick up later service. This allows you to save money on any delivery fees and avoid busy shops on the Black Friday itself."

Which? has also opened up its app for free for the next 30 days so bargain hunters can check its reviews before buying.

3. Know your rights

"The Consumer Rights Act, which is the law that covers this activity, clearly says that it doesn't matter if you buy something in the sales, your rights are the same," said Dean Dunham from Retail ADR, a non-profit organisation offering advice about retail disputes, on its website.

"If something goes wrong in the first 30 days, you have an automatic right to a refund. Thereafter, up to six months, you have a right to exchange/refund or to have it repaired, but unfortunately, the retailer gets to choose which one and after that you have to prove why it went wrong," he wrote.

In the UK, the Consumer Contracts Regulations gives online shoppers extra rights - for example you have 14 days to decide whether to cancel your order in addition to a 14 day returns period once your goods arrive, says Which?.

4. Avoid website crashes

Inevitably the huge amount of website traffic will result in some shopping sites being unable to cope.

Speaking to the BBC last year, MoneySavingExpert's deals editor Gary Caffell suggested keeping shopping sites open on more than one device, which might also help you keep your place in the online queues.

Many experts agree that the morning tends to be peak time, so afternoon shoppers may have an easier time - although by then some of the biggest bargains may have been snapped up already.

5. Hit the shops

If you can face the crowds, consider stepping away from the internet - according to payment processor WorldPay, this year's Black Friday could be worth as much as £1.35bn to UK high streets.

One advantage of heading out is that shop staff are also primed with knowledge about the best deals on the shop floor, says Olga Kotsur, CEO and founder of in-store technology firm Mercaux.

"Although Black Friday deals are largely advertised online, there are terrific deals to be found in-store," she said.

"Our advice to shoppers would be to not underestimate sales associates whose role has become increasingly intelligent and data-driven.

"Customers should leverage the knowledge of sales associates so they can find the best offers that are suited to them personally."

Of course if the whole retail frenzy leaves you cold you can always embrace Buy Nothing Day and join a protest against consumerism that started life in Canada in 1992.

Its website describes Black Friday as "an absurd dystopian phenomenon". It suggests locking up your wallet and staying at home with a good book instead.