Buyer being a Consument in light of article 221 of Civil Code, has a right to renouce a sales agreement without stating a reason in 100 days from the time of delivery. To save this right only thing needed is to provide a statement before renouncement period ends.
Product should be wrapped in protective wrap to prevent damage in transportation and sent on adress below:
Yoer Adrian Kazer
2/218 Bernardyńska Street
64-000 Kościan City
You can find additional information in User agreement.
You can find the required document here.