Shoemakers can do a lot to help you decide which size is right for you. They can feel in which places your foot is hard against the edge. They can judge the clearance at the instep by how far the laces tighten. And they can look for any slippage of your heel. In the case of Lodger, they can even scan your foot to compare the fit with different lasts electronically.

But in the end, the true arbiter of fit is you. Only you know where it squeezes, where it is loose and where it hurts.

So you need to understand how leather changes. As it is a skin, it will stretch under pressure and reform. To a certain extent it will shape to your foot. This is reduced the more seams there are – leather stretches, seams don’t. So a full brogue will adapt much less than a whole-cut.

As a general rule, then, it is worth getting the size of shoe that is a little bit small, rather than a little bit big.

I had this choice when trying on a pair of shoes recently. The size 8.5 was very comfortable, but it laced all the way up with no gap at all between the facings. So over time, I knew that the shoe would become a little loose. And the right (smaller) foot already had a very small amount of slippage at the heel. I’ve solved this problem in the past with tongue pads (see post here). But that is obviously less than ideal.

The size 8 had greater room to lace up, but was tight across the ball of the foot. Not painful, but a little uncomfortable. So what to do?

Well, fortunately I have two pairs of shoes to compare to: two Edward Greens (rebranded as Ralph Lauren), one a full brogue and one a monk strap, one in an 8.5 and one in an 9. The 8.5 took a fair amount of wearing in; it was uncomfortable for months. But it now fits perfectly and will last for decades. The 9, on the other hand, was incredibly comfortable from the start but is now a little large – it required an extra hole in the strap.

The choice, really, is yours. Sometimes a shoe will fit perfectly, but often one will be a little bit big and one a little bit small. Then you have to choose: fit now or fit later.

It is also a question of personal preference to an extent – don’t forget that. Some people prefer their shoes a little loose all the time. Think back over previous experience and try and work out which you prefer. And bear in mind that leather will stretch.