Nothing sophisticated. I use raw, cold pressed linseed oil, http://en.wikipedia.org/wiki/Linseed_oil , available here in Germany in better supermarkets because it is used as an ingredient in some meals. I dye the oil red using Alkanet root (alcanna tinctoria) http://en.wikipedia.org/wiki/Alkanna_tinctoria .Years ago my friendly local pharmacist ordered it for me, but I had to buy a package, a whole kilogram. IIRC it set me back about 25 Deutsche Mark (it is that long ago!) and I am still living with a good supply. The chopped alkanet root came as fairly coarse chips. I grind them into a powder using an old coffee mill. I drop about a tablespoon into a bottle with 250ml = half pint of linseed oil. Shake well and let stand for 2 weeks, shaking again once or twice. The root dyes the oil a deep red and settles on the bottom of the bottle. Decant. Apply liberally to the smooth wood, once a day. The oil at first simply diappears into the wood. After about 4 coats I apply an Oil drying agent from an art supply shop liberally and let dry for a day. Another thin coat of linseed , next day dryer again. Alternate oil and agent day by day for about a week. If accidentially oil builds up above the surface, let dry thoroughly and remove with fine steel wool. As a last step several coats of CCL Gunstock Conditioner give the desired sheen. Just patience and some experience.