The present invention provides a method of installing a foundation for an offshore wind turbine and a template for use herein. In illustrative embodiments, the template is releasably anchored in a seafloor and the template is leveled before installing a pile. In a method according to some illustrative embodiments herein, a template may be provided, the template comprising at least one hollow guiding element for receiving the pile, at least one suction bucket, a frame body to which the at least one hollow guiding element and the at least one suction bucket are coupled, and controlling means configured to supply a pressure to the at least one suction bucket. The method may comprise disposing the template on the seafloor, supplying a negative pressure to the at least one suction bucket for driving the suction bucket in to the seafloor, and controlling the negative pressure supplied to the at least one suction bucket to adjusting a penetration depth of the at least one suction bucket so as to level the frame relative to the seafloor.