How can I effectively paint over linseed oil to ensure proper adhesion and a smooth finish?

To effectively paint over linseed oil for proper adhesion and a smooth finish, you should first sand the surface to create a rough texture for the paint to grip onto. Then, apply a primer specifically designed for use over oil-based surfaces. Once the primer is dry, you can paint over it with your desired paint, making sure to apply thin, even coats and allowing each coat to dry completely before applying the next. This process will help ensure that the paint adheres well to the linseed oil surface and provides a smooth finish.