Pour 1 ounce of boiled linseed oil, available at craft stores, into a disposable pie pan.
Dip the tip of a large paintbrush into the oil. Soak up the oil with the bottom part of the bristles.
Apply the oil-soaked brush to the top right-hand corner of the blank canvas. Drag the brush down to the bottom of the canvas in one firm stroke.
Apply the brush to the left of the primed area, overlapping it slightly, and drag it down to the bottom in one stroke. Dip the brush into the linseed oil as needed to keep the bristles slicked.
Repeat the process in Steps 3 and 4 until the entire canvas has been primed with the boiled linseed oil. You can paint on the canvas immediately.
