Dry Brushing is probably my favorite nail trend from last year, all you need is a few different color nail polish with no other tool needed.
Basically, you need to apply a base color (I like using white since it's like a blank canvas that you can create your own piece of art on) and dry brush random color on. Dry Brushing is basically try to get rid of as much polish as possible from your nail polish brush and paint on random stroke, the brush stroke/lines is what make this so cool. There's no right or wrong just like art and east to do!
Silver Base here with metallic fuchsia and blue.