Which poses a bit of a challenge, because the typical file sharing client does, in fact, seed (upload) at least while downloading a resource via a P2P protocol.
So, to clarify, the "safe" option to exploit this peculiar trait of Swiss law is to not use a P2P protocol (i.e. not to use BitTorrent)
You should stream instead of downloading it. Most programs with which you download will have an upload too. If you stream, it's only temporarily downloaded to your computer, but you won't upload.
Depends on how the client is configured, if the seed ratio is set to 0 and upload at 0 kb/s then you upload precisely nothing. Obviously not in the spirit of torrenting but certainly easy to do.
Whether uploading is legal or not depends on the content.
In the OP's case it would technically be illegal to upload as TV shows and films will be copyright material in the vast majority of instances, but I've yet to hear of anybody successfully prosecuted for personal torrenting.
On the other hand with copyright free material, or material that's been released gratis then there is no issue with the uploading aspect.
I would never tell anyone to do anything illegal but I've heard that unsavoury sorts that do engage in such undesirable activties tend to use VPNs to cover their tracks.
In short, as has been already answered, to download content such as music or movies is legal, however to upload it is illegal. As BitTorrent is a P2P protocol, this means you are sharing content - that is both uploading and downloading. So technically, no, it is illegal.
If you stream the video/music however, it could be legal as there's upload, only download. I say could because programs such as Popcorntime use P2P to manage their streaming.
In the case of software, it is illegal to either download or upload.
Man, I feel ancient when everyone talks about the only downloading options being P2P. Back in my day, we use d the net differently, didn't have all these fancy P2P protocols and still managed to get our warez... I mean, movies.
TBH, the resources to police illegal downloading simply don't exist - law enforcement struggles to keep up with the dark web, so helping the film and music industry to maintain their obscene profit margins is not a high priority.
Every now and then, someone - typically running a server or torrent site - will get traced by the film / music industry and get sued aggressively, but this is more to make an example and frighten others than to make any real dent in the practice. Using a VPN will add an extra layer of obfuscation of course. You could even use the Tor network if you were ultra paranoid, but I wouldn't recommend it.
TBH, if you understand how P2P, and BitTorrent in particular, work, the film / music industry could have crippled it years ago. I'm actually surprised they haven't gotten their considerable resources and s**ts together to do so.