Before apply any product on to a wooden surface it must be clean and dry (moisture content max. 20%).
Any old varnish or lacquer is to be removed by sanding and small holes, cracks or dents must be filled with a Woodfiller (Osmo Woodfiller for up to 2mm in depth). then sand carefully, Remove dust with a vacuum before application.
Depending on the type of surface you may need a very rough or medium sand paper, Once properly sanded the surface will be very smooth and you will be able to feel the wood's natural fibres.
The surface should feel smooth along the grain but blunt against the grain, It is very important to always work with and along the wood's grain this ensure a perfect result.