Hi Despina, a friend of mine lives in Lausanne and offered a few tips. Hope it helps
Bars
Great Escape (decent irish pub; have a nice courtyard; busy and fun in the evenings) -
www.the-great.ch/
Etoile Blanche (decent pub/restaurant; busy and fun in the evenings -
www.etoileblanche.ch/
Bourg Plage (only summer; more chilled, sometimes concerts)
Bar Tabac (quite, chilled bar/cafe) -
http://www.bartabac.ch
Restaurants
Le petite boeuf (good for grilled beef (grilling yourself on your own grill) or beef tartare; a bit pricy, but nice experience having a grill on your table, good meat)
Brasserie les Trois Rois (Steak Parisienne or Beef Tartare)
Cafe du Simplon (good value for money; solid food)
Bazart (Tapas; reasonably priced)
Cully (10min from Lausanne by the S1 or S3 train) - cosy little vine town/village
Cafe de la Post (Decent food for a reasonable price)
Clubs
Cinema de Bourg (small cinema turned into a club; have sometimes cool funk nights) -
http://www.le-bourg.ch/programme/
La Ruche (usually good electro sounds or theme nights; smaller clubs -
http://www.la-ruche.ch/
Buzz (Cellar club; more mainstream music) -
www.buzz-club.ch
In the flon area there are couple of bigger clubs (e.g. Mad, D!, Loft), but not my favourite. Usually very young.
Beaches
Theatre de Vidy
My favourite ones are outside Lausanne: 1) Lutry plage (Go to Lutry - 5min by S1/S3 train away from Lausanne; From Lutry train station walk down to the lake and keep left) with Bar/BBQ right at the beach, 2) Espesses (10min by S1/S3 train away from Lausanne; From Lutry train station walk down to the lake and go right until you reach nice green spots at the lake).
I usually get a disposable grill and take BBQ stuff with me as well as some vine. Manor food is a very nice supermarket in town, where you good really good food and vine. At Lutry plage rent out a kayak or go for some stand-up paddling. Defintely take your swim gear and go for a swim in the lake.
Other things recommended:
If there is nice weather, go to Flon and rent out bikes (below the bridge next to shop Ochsner sport; bring your ID and CHF 10,- deposit per bike).
Exlore city by bike - e.g. cathedrale, Olympic park). Bike down to lake and then either go along the lake to Morges (nice bike ride along the lake; ca. 1hr) or go Lutry/Cully, Lavaux to Vevey through vineyards (Vineyards in this area are world cultural heritage; great view on the lake and Lausanne; on the way you can make to stops in the wine bars and cellars; 3-4hr assuming some stops or take the train to Lutry/Cully and bike from there to Vevey which cuts time in 1/2).
You can also visit Montreux and then the train from Montreux to the top of Rochers-de-Naye (over 2000 metres). Great view 360 degree view with view on the lake and Lausanne as well as Valais mountains. For the sporty ones go with train to Caux and then hike up the mountain (ca. 2 1/2hr).