'I photographed Bowie with Twiggy for Vogue. But he ended up taking it for the cover of Pin Ups'

I started going out with Twiggy in 1965. She wanted to become a model, so we arranged meetings with fashion editors, but they all said she looked too young. Eventually she got her break, and the whole look of the era changed: all the girls wanted hair and eye makeup like hers.

By 1973, we were no longer a couple, but I remained her manager. David Bowie's Aladdin Sane had just come out, and we loved the line: "Twig the wonder kid." We met Bowie a few times socially, and he mentioned that he wanted to be the first man on the cover of Vogue. I called them to suggest this, with Twiggy, of course, and after a bit of a hoo-ha, they agreed.

To be honest, I wasn't a professional photographer. I had watched Bert Stern, a hero of mine, do a cover with Twigs. I was fascinated by the set up: he would disappear into an office while the assistants set everything up. Then, when it was ready, he would return, utter those immortal words, "Strike a pose", click the picture and go. I thought: "Justin, you can do that." That's the moment I became a photographer.

Bowie was working on Pin Ups in Paris, so we flew there to do the shoot. When Twigs and Bowie were together and lit up, I looked through the viewfinder and realised that David was pure white, whereas Twiggy was tanned from a holiday in Bermuda. There was a moment of panic because I knew it would look bizarre; but the makeup artist suggested drawing masks on them, and this worked out even better.

I remember distinctly that I'd got it with the first shot. It was too good to be true. When I showed Bowie the test Polaroids, he asked if he could use it for the Pin Ups record sleeve. I said: "I don't think so, since this is for Vogue. How many albums do you think you will sell?" "A million," he replied. "This is your next album cover!" I said. When I got back to London and told Vogue, they never spoke to me again. Several weeks later, Twigs and I were driving along Sunset Boulevard and we passed a 60ft billboard of the picture. I knew I had made the right decision.

CV

Born: 1939, London.

Influences: Richard Avedon, Bert Stern, Willie Christie.

High point: "This and my pictures for the design store Biba, which are iconic of the 1970s."

Low point: "When the partnership with Twigs ended."

Top tip: "Watch the composition of your picture; make sure you get the balance right."