I have 2 inexpensive studio umbrella lights and a metal adjustable rack that can be used to hang fabric or any other type of backdrop. The lights help but the most important thing is to learn to use your cameras manual settings correctly. An iPhone also will take pretty decent photos but they aren’t high resolution or large in size. I do think it is important to invest the time and a little money in your photography because your future clients will see your photos before ever seeing your cakes in real life in most cases. See if they have cowboy studio lights maybe on your amazon UK site. That brand is inexpensive in the US on amazon and works really well.
Bliss Pastry, Deland, Florida https://www.facebook.com/pages/Bliss-Pastry/123883354373830