your probably finished by now but spar varnish,linseed or tung oil and
turpentine mixed and heated . brush or wipe on liberallty , let set till
tacky, the wipe off . reaply every 24 hours till you have 3 or 4 coats.
you can use more varnish and less oil on each consecutive coat.
Wait about a week then wax with bowling alley wax.
On course grain woods like oak, you can sand between coats ,creates a slurry which fills the grain and leave it smooth as glass. can also
us steel wool to apply . Didn't mean to write a book!!!!!!!