Getting ready for the Flower Show #2 - Preserves

Chased out of the garden by the rain and in a bid to be super organised for the Flower Show this year, I thought I'd have a go at making jam today. Thinking back to my previous efforts - like last year's rhubarb and ginger effort which I knocked up in a hurry the night before the show and slightly burnt in the process - it tasted OK but was unplaced in the judging, if you're interested :) - I thought a bit of extra time for troubleshooting would be a good idea. As I don't have a particularly sweet tooth, I thought I'd go for the Chilli Jam category so have had a lovely afternoon bubbling away in the kitchen while it rained outside. Turns out the extra troubleshooting time was a good idea as I don't think it's setting very successfully - any top tips out there from experienced jam makers?
Take a look at what you can enter in the Flower Show Industrial Preserves section on the website -jams, jellies, chutneys, honey, drinks and fruit curds. It's really fun to take part and as you can see, you don't need to be an expert!