One caveat is that either your client and router both have to support UPnP, or you have to manually open up a port for UDP traffic in your router and forward that to the machine you're running the client on.
I also use transmission-create to make torrents from the cli, but the UI of your client will have an option.
I use magnets to transfer all large files - although if there's anything confidential in the file, encrypt it first. The only thing keeping people from plucking your files out of the ether is a lack of interest.
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[1] Such as https://newtrackon.com/list
[2] Which are magnet:?xt=urn:btih:[insert torrent hash here]
Torrent hashes can be found in the UI of your client, or at the beginning of the actual .torrent file.