As you can see you can use a wide variety of paint for this technique. Just experiment. In this mix I have tester pots of emulsion paint. Good and cheap. You will also need an old credit card to swipe with.
The tester pots are the first ones I will use. But you could mix them up. First put some blobs of paint along one edge of the paper.
Then swipe the colours across the page. Try not to mix the colours too much otherwise they may become rather muddy.
Continue to swipe until you are happy or the paper is covered. If you have used acrylics you can always add more colours once the first are dried.
This is using some acrylic artist paints.
Swiping these colours.
Some more examples.
And then you can stamp onto sections you like to create whatever you like. Here is a card I made where I stamped onto a background paper I had made. (sorry the photo is a little out of focus.)
Quite effective when you see the result like this particularly if you choose the section carefully.
Have an experiment and see what you can come up with. Try using different paints.