Start with the service workflow
Map what happens from scan to service before printing QR codes. Decide whether guests can only browse, place an order, request a waiter, ask for the bill or pay. Assign one staff owner for incoming requests during every shift.
Design the menu for decisions
Use short categories, readable prices, concise descriptions and clear allergen information. Mark unavailable items immediately. Translate the actual menu content—not only navigation—and have a fluent reviewer check every language.
Test the busy-service failure modes
Test weak Wi-Fi, repeated taps, two guests ordering at once, a sold-out item, a delayed kitchen response and a lost connection. Staff need a large, unmistakable new-order alert plus a visible queue that survives page refreshes.