Very shortly after your order is placed, it is assigned a tracking number. If you have a USPS tracking number that is not showing movement, or the search result is "Awaiting Package," it is likely your order was shipped using what is called last-mile USPS delivery. This means your order was shipped using DHL, FedEx Ground Economy, or UPS SurePost/Mail Innovations to your local USPS sorting facility. Your order will be delivered by USPS.
If your USPS tracking number is not showing movement, try searching the same tracking number on DHL eCommerce, FedEx or UPS. The package may be in transit, but has not yet been received at your local USPS facility.