That's this one?
http://www.machinemart.co.uk/shop/product/details/010110125#reviews
First point is this m/c has a low end output of 35 Amps; 30A would have been easier to learn with. This doesn't make it impossible to weld thin body panels with, but does make it a bit more difficult, especially if you are learning.
On these cheaper machines the lower amperage setting is quite important; some big pro machines can run and weld thin panels at 35A or even 40 without problems.
To give yourself the best start, use an Argon/CO2 mix like BOC Argoshield light, and for 0.6mm gas wire something like this:
http://www.weldequip.com/5kg-mig-wire.htm
The small gas bottles from MachineMart or Halfords etc only give a few minutes welding time for something like £15 a toss, so don't use these unless you really have to, they are very expensive.
Start by reading the tutorials on here, and watching some on Youtube, etc. Use 2-3mm thick steel for your first practice runs, as you need to get used to laying beads on the flat before starting anything more advanced, and you may blow through anything thinner to start with. As you get better you can move down to 1-2mm, and then to panel thickness, which can be anything from 1mm down to 0.5mm.
Best of luck with it, you have got a machine that is not the easiest to learn with, but it can be done. One place I worked at had a Sealey with a low of 35A, so guys either had to learn how to use it for car panel work or take a walk up the road....
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