Usually, I use a fatter cap on a high pressure can, then I hold my trigger finger half way over the front of the tip while I spray. It's messy, but it makes for a good splatter. To get some serious drips, I would hold the can right up against the surface and angle it down.
It all comes down to experimentation. Remember, there is no wrong way to paint!
Whenever I strap in, all I think about is how I can have the most fun.