Yes pretty much, I get my borax from boots, if you look in the household cleaning section you get boxes of it there. If you cant find it then ask, it will be in a white box with some blue stripes if i remember correctly. I dont use the paints they talk about though, I tried them and found them to dry far to quickly and blotch up. The humbrol stuff seems to be the best i have found sofar.
In my pictures you will see many differant swirls, most of them do NOT have white undercoats, think about how colours interact and try things out, the blue mc's have a light blue undercoat, the yellow/red/orange have a yellow undercoat and so on, you can get some really nice effects if you just try things out.
I first put coloured undercoats on when I tried the GMC, and found the white showing through, so i sprayed it green first and it came out how i wanted as the green didnt show through the black, it just made the green come out in differant shades (As shown in teh video)
Hope this helps. I may be doing some more in teh summer and if i do i will write my tutorial which I have been trying to do foor a while.