Breaking in a pair of Doctor Martens?

[Feek]

I've got a pair of DMs that I bought a few years ago and wore once. I had them on for a couple of hours and in that time I got such huge blisters that I've been scared to go back to them since.

When I was a lad I used to wear DM boots all the time and I'd decided to get some more, I don't recall having this trouble getting them broken in all that time ago. It occurred to me yesterday that they're still at the bottom of the wardrobe and I ought to do something about it as they'd be dead useful with the weather as it is.

What's going to be the best way to break them in? Hot bath, set fire to them, wear them for a few minutes a day, increasing gradually *yawn*

Spec me a breaking in method for a pair of high DM leather boots.