Are you kidding me?

Should we list every one of them?

Haha, fair enough.
How about specifically in the Schaffausen area, and I guess Milan will be pretty straightforward..? Maybe a better question to ask would be what should we (two 19 year old Canadian girls) avoid?

I went on a Contiki tour last summer and we went to those countries these are the places we went too:

Switzerland: Lucerne- The beach club! amazing bar/club with sand all over the floor!
Italy: Florence- The Discoteque! Its a huge dance club with a bar and kareoke lounge downstairs! A great time had by all!
The Red Garter is also a great kareoke bar in florence.

Okay, it’s been a few weeks, and no one answered your question, just as I expected:
 
Clubs come and go, and few backpackers will remember any names of specific places.  In this case, it looks like no one knows nor remembers specific names of places in Milan and Schaffhausen.
 
Such a question is one you should ask after you arrive in a particular city.  Not before going there.  So…ask around when you get there, and have fun.

If the nightlife is your biggest concern, then ask around for what hostels in those areas have the best social events/aspects…

That will usually lead to a pretty fun and interesting night and is an easy way to meet a group of people…..