Welcome to the wonderful world of black and white stripes. The countless illusions that this pattern creates is amazing. They're pretty tricky to use but once you've got the hang of it you'll have no problem working with this in no time.
For starters, try putting on a solid color. This tames the pattern down and creates an "unexpected color pop".
Enter the difficult part: working with an entire striped piece. I try to to pick vertical stripes like this one from TB Dress, just because these give an illusion of a leaner figure. While horizontal ones makes it look wider. That's a general rule of thumb.
The great thing about stripes is that it generally has direction. May it be up to down or left to right the eyes can easily follow the pattern creating that illusion. So it has endless possibilities even when you're playing with slanted lines it still creates form when used correctly.
TB Dress Striped Dress
Bazaar Black Bow Flats