Mixing patterns is still very much a trend. During the warm weather when sometimes you have less space to spread out those patterns (skimpier clothing), it can get difficult to do that. My theory is to keep your color palette limited and your patterns similar.
Color palette: B&W and green
Patterns: solids and stripes
Solid white shorts with an oversized striped top. Add B&W striped shoes in a different stripe pattern. Round stud earrings in a saturated green stand up well to all this B&W. So let's do the same green in a bracelet that mimics stripes. And we'll add a clutch in a solid green with a black strip that mimics a stripe as well. To finish this off, add on the B&W striped sunglasses. That gives you 3 different stripe patterns, 3 colors, and many ways it all relates and looks great!