After considering the options, I went to my local Wilkinsons and bought a fermentation bin, some odds and sods and an Edme German lager kit. Now don't knock it, I know it's not real beer, but I have to consider everyone who's likely to be at the BBQ, and most of my friends either drink cider or lager!
The instructions called for 1kg of sugar, preferably brewers sugar, and when I looked into it, it's inverted or partially inverted sugar - I know that tate and lyle golden syrup is inverted sugar, so I decided to buy two tins of tate and lyle golden syrup - I got two 454g tins (making a total of 2lb's sugar, or 908g) - a bit short, but it means I get a slightly less alcoholic drink, but it's my first step on the learning curve!
Here's everything getting ready for sterilization - my bathroom has become the brew room!
Tins of syrup and the lager kit in a pan of hot water while I clean everything
A few minutes later, everything sterilized and rinsed, I boiled the kettle to get my 3.5L of boiling hot water and poured it into the fermenter, opened the cans and added them in as well, then a good stir with the long spoon
I topped up to 22L (5Gal) with cold water from the tap and checked the temperature - 21degrees C
Then the sciencey bit - I poured some of mix (wort?) into a sterilized and rinsed jug and then into my trial jar to get an initial hygrometer reading, the remainder in the jug had yeast poured into it to act as a starter and left for 5 minutes while I cleaned up and prepped the airlocks. In went the yeast and the lid on
As Aleksandr would say: "Simples!"
Initial Hydrometer reading: 1.034 (label says starting gravity should be around 1.040 - 1.043) - so perhaps I needed to add more sugar, further investigation on the interweb and people are recommending to add 15-25% to the recommended weight of sugar, if using golden syrup. I'll let it continue on it's merry fermentation and chalk that up to experience.
I wondered how long I'd have to wait before I get some yeast action, and 'tinterweb said 1-3 days. After checking the airlock a couple of times within an hour of loading the yeast in, I thought the water level had moved a bit, but I wasn't sure. The good lady tells me that when she went to the loo at 2am, it went "buh-bluhb" more than once and this morning it was bubbling merrily along letting a bubble through every minute or so!