Don't forget to drop the leading zero - dialing CH->AU or AU->CH. Actually 99% of places drop the leading zero on international calls, so you probably know this already.
If your Swiss telephone number is for example 055 246 42 22 a person residing Australia could call it from there mobile phone entering +41 55 246 42 22 or which is also possible entering 0011 41 55 246 42 22 The latter method should work from any Australian telephone.
The pattern should be easy to spot. Drop the leading zero and perpend either +41 or 0011 41 to the number.
Like wise if you want call Australia from a Swiss phone you could either use +61-prefix if it supports it (like mobile or IP phones). If not supported you can use the 0061 prefix on any Swiss phone.
Pro tip: If you store all Swiss numbers on your mobile phone using the +41-prefix (with dropped leading zero) you should not have E.T.s problem and phone home from anywhere. And like wise for numbers from other countries https://en.wikipedia.org/wiki/List_o..._calling_codes
Just one things remains to known: Why does a person in Australia wish to call the Bachtel Lopienschnurri ?
We have reached perfection! It took 13 years until no expat had questions anymore - but because it was so much fun, we start all over with the old ones.