From Beirut take bus #6 going from Cola station to Byblos (Jbeil). Ask to get off in Jounieh. It is possible to catch the bus anywhere on its route, including at the Barbir intersection in central Beirut. The ride takes between 20 and 45 minutes depending on traffic and costs around 2,500 LL.
From the Rafic Hariri International Airport your best bet is to take a taxi for around 25,000 LL.
Public transportation in the city of Jounieh is just like any other city in Lebanon. It's quasi absent. Your best bet would be the famous "service" which is some sort of public cheap car share system. Service cars usually have red plate colours with the letter P.
Otherwise, a car is essential in order to move around comfortably although Jounieh is a pretty walkable city with well maintained sidewalks and green areas.
Jounieh's main sights include: The old port and bay of Jounieh, the old stone souks, Our Lady of Lebanon & Casino du Liban.
You can do all sorts of things day or night ranging from visiting the city's several restaurants with all kinds of cuisines from Italian to Japanese cuisine or just sitting at one of the many coffee shops to relax and have some narguileh or visiting the bars and night clubs.
Jounieh has a special culture of chillaxing by sea. There are many resto-pubs all along the bay coast that offer a wide selection of alcoholic and non alcoholic drinks and appetizers to enjoy the sea and the mountains at one single place.
Jounieh is a relatively big residential and commercial city. All sorts of shops are open everywhere especially in the old stone souks. You can buy clothes and shoes, artifacts, souvenirs, fishing equipment, agricultural products, etc...
There are tons of street food kiosks scattered all over the city. There's a main parking lot in the Kaslik neighbourhood of Jounieh with dozens of street food kiosks. The old town also has a nice selection of restaurants and the resto-pubs along the bay all offer fine food with a wide selection.
The ATCL district of Jounieh is a nice drive with wide sidewalks that is dotted with restaurants: Rassifouna, Provincial, Al-Baladi, etc...
Some popular restaurants in jounieh: Saniour sea view (Sahel Alma district), La crêperie (high end - Kaslik district), Crepaway (Kaslik and Sahel Alma highway), Sushi Star (Ghazir highway), Malak el Taouk (popular street food chain - several locations: fouad chehab, chir, zouk mosbeh highway).
As mentioned before, Jounieh is a popular nightlife destination. Most places are located in the city center around the old stone souks.
Some popular clubs/pubs: fertil, hooligans, etc...
Being a top touristic destination, Jounieh harbours a lot of hotels. Many lie along the sea and others are more inland. The Maameltein district is known for having many cabarets.
Popular hotels: Bel Azur, Reston hotel, Burj on bay, etc...