Make sure you also visit Lake Bohinj. It's Lake Bled's not so glamorous cousin and it's less crowded and in many ways more authentic. It's a short drive from Bled and a great location for a chiller summer holiday!
If you want to drive on the country's motorways, you MUST buy a the toll sticker called vignette. These are available at any petrol station and I think we only paid €15. If like us, you're renting a car in another country and driving it into Slovenia, you have to declare it to the rental agency. They will equip you with the proper insurance.
A part from the views, we were not crazy for Bled Castle. If you are short on time, you can give it a miss.
Everyone speaks English quite well but here are a few basic phrases to get you started. Zdravo which means ‘Hello’; Hvala means ‘Thank you’; Prosim is ‘Please’; Oprostite is “Excuse Me” and Ja and No for ‘Yes’ and ‘No’.
Vinoteca Movia has a great selection of wine and they are very willing to explain everything about Slovenian wine. Great place to visit.
Postojna cave and castle are on the way to Ljubljana if you are driving from Italy. If you have 4/5 hours to spare, make sure you stop there.
Absolutely try the Cremeschnitte at Bled. And if the weather holds you can swim in the lake even to the small island in the middle.