Well, I'm not Kam, but there are a few ways of going about this.
They all involve sizing the designs to the dimensions of a minifigure element (be it torso, arms, legs or head) and printing it in colour on some kind of paper - be this ordinary paper, sticker paper, labels, inkjet waterslide decal paper or using an ALPS printer to print on waterslide decal paper.
I'll go through the motions of all of these.
Firstly, some people print on paper and glue it to their minifigures. This is cheap and relatively easy, but it is also sometimes messy and doesn't really look as good as it could.
Secondly, others print on labels or sticker paper. This requires simply a 'high quality' setting on your printer for good quality and then, once printed, simply peel off and stick on. Labels aren't too expensive, and this is easy and looks very good in some instances, although matching colours to the background of the element is hard.
Thirdly, there is inkjet waterslide decal paper. This is what I use - it's a bit more expensive than sticker paper, but the results speak for themselves:

Basically, you need to print (in this case) on clear waterslide decal paper with some special settings. This varies from printer to printer, but it's generally something to do with "glossy". Then, once printed, you need to seal the ink onto the paper with a sealant, such as Keen's Crystal Clear Acrylic Spray or Krylon's. After some time (about a day) you can then cut out these decals, dip them into water, and slide them onto the blank element. (Kam has excellent tutorials on his site - I suggest you check them out, like
this one.) Then, once this has dried onto the element, you can seal it onto the element with the same spray. After this has finished drying, you have a decalled and very professional-looking piece.
There is also white waterslide decal paper, which works much the same - you just need to do a coloured background for your decal, just like sticker paper. The application is the same as with clear paper.
There is another way, but it's almost impossible and it's very, very expensive. You could try and find an ALPS printer - apparently they aren't even made anymore - and do what Kam does, which is print onto a special kind of waterslide decal paper and 'underprint' white ink under the colours, which means that they show up on dark elements. You see, the problem with clear inkjet paper is that it is transparent - so the colours only show up on light coloured elements; for example, white or light tan.
As I said, an ALPS printer either can't be found or costs around £500 or so, and is very complicated. However, if you're lucky enough to be able to afford and to find one, Kam should be able to help you in using it.
So, I hope that all helped you in some form.
- CG