Study and observe the wood patterns on old barns, antiques and old pine flooring. This will give you a better idea of what aging does to wood. Observe the location of marks, nicks and scratches, including how often they appear on an individual board.
Chisel small nicks into your boards. Use a hammer to make indentations, as well as throw a sock full of rocks onto the boards a few times. Dragging a heavy chain across the boards make interesting scratches. Ice picks or drills can simulate old worm holes. Do not become overzealous, know when to stop.
Sand sharp edges and uneven areas with sandpaper. If the distressing has created wood splinters, sand them off.
Place one piece of steel wool in a jar of vinegar. Allow the steel wool to sit in the vinegar for about 24 hours, until part of it has dissolved.
Prepare a cup of black tea. Paint the tea over the boards as this releases tannins. Allow tea to dry for about one hour.
Paint the steel wool and vinegar solution over the boards. Combing these products will instantly give the wood an old and dark appearance, it will no longer look like bright pine. Lightly sand the wood if you would like the color to look somewhat lighter.