Software product lines (SPL) are a powerful way of ensuring quality, economic efficiency, and manageability of software system families. In SPL, a key aspect is the domain implementation, whose goal is to provide the implementation of reusable assets (components). However, current approaches present some gaps in this direction, such as the lack of definition on how to implement and document software components in a systematic way. In this context, this paper presents a method for domain implementation in software product lines. The method is based on a well defined set of guidelines, inputs, outputs, and roles, and uses OSGi as the main implementation technology. An experimental study evaluates the viability of the use of the method and the impact of applying it to a software development project.