Plain and simple: Leave the A1/E61 motorway at Unec and take the road 212 thru Cerknica, Nova vas and Sodražica.
Or vice versa.
Or forth and back… 🙂
Or forth and back with a break at Bloško jezero (pictured). 😀 In Nova vas look for an intersection for Bloško jezero (45.786450, 14.514858).