The Premium Shop sells timed boons for Wraithgold: Incense (wild creatures return twice as often, 30 days), Bait (halves the respawn interval, stacks with Incense) and extra Auto PvP attacks for the day. The store itself is not open yet - the shelves are there, the till is not; this page shows what you will find when it opens.
1Open the shop
Open the MENU and pick PREMIUM SHOP.
2Your Wraithgold and the shelves
Your Wraithgold balance is at the top right. Each shelf is one item with its price and how long it runs; a boon you already hold shows its remaining days. Until the store opens, buying is off - the shelves are a preview.
3The Shadow Trader lives here too
The SHADOW TRADER tab at the top of the counter is open now - he takes your other currencies and pays one out each week. See the Shadow Trader tutorial.
Screenshots are taken from the live game by tools/tutorial_shots_b.py (dfmc-client) and regenerated after interface changes. The rules behind each screen: system-premium-shop.