You're opening with nothing but a permit and some cash.
1. Buy a licence and order stock from the shop menu.
2. Build shelves and a checkout with the hammer (freezers for cold goods!).
3. Grab boxes from the cargo bay (top) and stock your fixtures.
4. Tap OPEN STORE — then scan customers at the checkout.
Open and close freely; tap END DAY when you're done.
Tap anything — fixtures, shoppers, pallets — to inspect it.