Mar 30, 2016 - 5:56 AM
Welcome back maciejjacek,
You can consider the Bernese Oberland/Jungfrau region, the Lake Geneva region and Graubünden. Please see the "Where to go" and "What to do" items in the top menu to get started. Also this page helps with creating a plan. The best itinerary depends on your interests, budget and travel dates, so it's best to first create a plan and then get back here for feedback.
I moved your thread from the Trip Reports forum to the Miscellaneous forum. The Trip Reports forum is to report back about completed trips, so feel free to post there after your trip!