For this nail art look I decided to focus my right hand nails around Hallows and my left hand nails around Horcruxes.
The right (Hallows) hand:
I first applied my base coat and base colour, Twilight Black Tie to all my nails.
For my pinkie I drew the Deathly Hallows sign with Stargazer 232 polish.
For my ring finger nail represents the Invisibility Cloak, so I used a mixture of Collection 2000 Sparkle Top Coat, elf Twinkle and NYX Grafitti.
My middle finger nail represents the Elder Wand, I used Revlon Nude Chic for the wand and added the sparkly polishes I used on the previous nail, to the background.
My index finger represents the Ressurection Stone. I used Andrea Fulerton Nail Boutique Trio in Smile in a Storm to create a diamond shape. Next, I filled two opposite triangles of the diamond with Andrea Fulerton Nail Boutique Stripe & Sparkle in Pattie. Finally I used Stripe & Sparkle in Katleen to draw the Deathly Hallows sign.
For my thumb, I used Stargazer 237 and used an image on Google to copy the HP.
The left (Horcruxes) hand: