For all the controversy surrounding various members of the Royal Family recently, the fact remains that few things sell as well at auction as items with a Royal connection. The closer to the Monarch, the better, as the silver cigarette case and letter from King George VI to Lionel Logue, his speech therapist, showed recently at auction when it sold for over £60,000. As you may  remember, the relationship between the King and Logue was the central theme of the film The King’s Speech.

Now we have the exciting spectacle of Princess Margaret and Lord Snowdon’s personal belongings coming under the hammer. In this case, not only are we talking about the Queen’s sister, but also about a glamorous society couple with a notoriously scandalous lifestyle that led to divorce.

In cases like these, what fascinates is not the expensive furniture, jewellery and pictures but the knick-knacks, toys and other highly personal trinkets that shed light on the personalities behind the public personae.

So what do we have here? A Snowdon photograph of a natterjack toad climbing out of a glass tumbler, an Inuit soapstone model of a walrus, a framed Punch cartoon, a brass fire helmet and three silver-plated and warthog-tusk masks from the Snowdons’ 1965 Uganda tour. Make of these what you will.

Two pairs of rather ordinary spectacles offered at auction, nine months apart. One sold for £137,000, the other for almost twice as much at £260,000. What is the difference?

The first pair, green-tinted and missing a screw, had been left in the back of Ringo Starr’s Mercedes in the summer of 1968. Of course they belonged to John Lennon, outspoken self-appointed leader of The Beatles and one of the nation’s foremost cultural icons of the 20th century.

It was not just that they were Lennon’s that made them so expensive, however; it was really because the specs themselves were the defining feature of his physical persona – the accessory from which he was instantly identifiable and so, really, considered a part of his personality itself.

The same, too, can be said for the second pair of spectacles; also small, round and a defining part of their owner’s persona. Of course, I am talking here about the pair belonging to Gandhi that sold at auction in Bristol in August.

Like Lennon, Gandhi was a cultural icon, and while Lennon was to a degree an anti-establishment political figure, Gandhi was the global personification of this phenomenon.

In both cases, what we are talking about here are ‘religious’ relics, items representing ideals that resonate so much with our contemporary consciousness that they are imbued with an almost magical ability to provide a direct link to the extraordinary figures whose faces they once graced.

Recently I started writing about how to bid online. Here are the next steps.

If you are going to be bidding live online, with an auctioneer acknowledging the bids in the saleroom, log on in plenty of time, whether through the bidding platform or the auction house’s own bidding service. Make sure you have the sound switched on. In many cases you will actually be able to see the auctioneer on screen.

You should already be aware of the terms and conditions regarding collection and delivery, as well as the buyer’s premium – the fee you will pay on top of the hammer price. Having considered all of this, you should set yourself a maximum bid for the lot or lots you want and stick to it.

When the auction starts, the current bid for the lot being sold at that moment will appear on screen and, below it or next to it, the asking price for the next bid. Below that you will see a button that allows you to make a bid and, to the right a list of lots coming up.

Because you are registered, any bid you make that is accepted will automatically be identified as coming from you. However, because you are bidding online, your identity will not be revealed to anyone but the auctioneer.

If you want to try before you buy, log on and watch an auction first. You can do this without having to register to bid.

We have been talking more and more about online bidding in recent weeks, but how do you go about it?

The first thing to do is find something you want to buy. You can do this ether by browsing an auctioneer’s website directly, or by looking at one of the auction portals, which gives access to numerous sales. If you have something specific in mind, you can conduct an online search for it in much the same way you would look for a new home via a property website like Rightmove.

When you have found what you want to bid on, click on the online catalogue entry and check the description, estimate and image – these days you should be able to expand the image to check details. Make sure you check out its condition, if that could be an issue. Details of this may be included in the description or there may be a condition report request button, which allows you to send an email direct to the specialist to ask.

Once you are satisfied with that, double check the sale details – date, time, who to register with (auction house or bidding platform), the deadline for registering and what you will need to register (credit card, ID etc).

Further details on what to do tomorrow.