Medium - Adding linseed oil alone to a color will increase the flow but won't give the sharpest edges. Adding thinner alone gives sharp edges but a chalky appearance. A medium of HALF CITRUS THINNER AND HALF LINSEED OIL is best for most situations.
Polyurethane is too finicky, the application is difficult and it doesn't give the look I want for my DIY furniture projects. Instead, I use an easy to an easy to make DIY top coat that provides a flawless finish every time!
10 Paint Secrets (PART THREE!): what you never knew about paint. You just add a little bit of Floetrol to your latex paint, and it prevents brush marks. For oil based paints, you can use a similar product called Penetrol
paint thinner on a file cabinet - taking it down to its natural metal jmoinajo edit: if you wait to seal it, you will get strange rust patterns from humidity. Seal with a clear gloss as soon as you like what you see.