You can choose any shipping method for your shipments according the delivery time requirements of Fyndiq's General Terms and Conditions for Merchants. Any cost or fees for shipment of the product to the customer are to be included in the calculation of the product price listed on Fyndiq and are carried by you as the merchant.
Note that all orders are to be shipped in 24 hours on a work day. For weekends this means orders received on Friday at 11 in the morning are to be shipped latest at 11 on the following Monday. Speedy delivery of your products will probably reflect positively in the ratings of your products by customers.
A traceable shipment is a letter or package sent with a fully traceable tracking ID, where an ID check is required upon delivery. Please note that Postnord varubrev is not considered fully traceable.