First of all you should maybe decide which dialect you would like to learn since Swiss German is not the same in every canton (region). Bernese German, for example, sounds different than Zurich German.
Since swiss German doesn't have fixed rules for writing (we just write everything how we say it) and is mainly a spoken language (documents, books, websites etc. are all written in Standard German) it's important to learn how to speak...so the best thing you can do is go to Switzerland.
There are some tv shows, programmes and some movies that are in Swiss German though...you could try to watch those with subtitles and try to learn words like that.
It would be really helpful to learn Standard German first though. Swiss German has the exact same grammar rules exept that there are only 4 tenses and some words are different.
I hope this helps a bit :)