How to claim
You need to pay for the goods first, then claim the tax back when you leave the country:
When paying for goods at the check
out in a shop, ask the assistant for a Tax Free shopping voucher.
Present the voucher to a Czech customs official within 30 days of the date of purchase to get a stamp. You can do this at Prague Airport
when you leave. The office is located BEFORE passport control.
Hand the voucher in AFTER passport control
to one of the Duty Free Shops. They will
then refund your VAT, minus their commission.