While in Vicenza I highly recommend the 40 minute hike from the centre of town up to the outskirts where Renaissance villas reign over the countryside.
You can Google Map your walking/driving route from the centre of Vicenza however I recommend you walk if you can manage a gorgeous stroll of 80 minutes all together.
If driving from Vicenza, take South (highway S 247) direction Riviera Berica - Longare.
Take Viale Margherita, then at the roundabout the via Borgo Berga on 1200m and finally the via della Rotonda.
Villa Valmarana is just 5 minutes walk from the villa La Rotonda, and best to park in the Valmorana because parking to the Rotonda is difficult.