Two techniques here on show: Ombré and Chevron. 

Ombré is using 5 shades across your nails (rather than as a gradient which is multiple shades across a single nail). I must say I’m guilty of mixing up these terms!
Chevron is a v-shaped line across the nail, but not a zig-zag or a triangle at the base/tip of the nail. 
I went for a grey ombré as I have plenty of grey shades. However I didn’t have quite the range I thought as some were very similar and one was dried out! A little franken and application of thinner and I was ready to go. 
Rimmel – Black Out
Dior – Gris Montaigne
17 – Chaperone (franken with Rimmel)
OPI – Skull & Glossbones
Essie – Blanc
Nails Inc – Electric Avenue
It’s a relatively simple process: paint one nail each colour and wait for them to be completely dry. Totally dry or you’ll mess it up in step two! 
Next use tape (nail tape, scotch or washi tape, whatever you have) to mask a chevron and paint the contrasting colour. Remove the tape straight away so you get a clean line. Topcoat when dry. 

Done! Looks pretty awesome 🙂