Welcome - another Swiss rider - we really all should meet up for a beer some time. Funny you said it was cheaper - the joy of exchange rates. When I bought mine a few years ago it was about 30% cheaper here than in the UK! How times change.
Now for the joy of Swiss importation. First, much depends on your status. If you are with an international organisation like the UN it is relatively straightforward. You will need
1) a handbook in French, German or Itallian (depending on your canton) - get one from your local dealer. If they are in a good mood, you can sometimes blag a free copy. I have a spare french one floating about that you can have if you PM me,
2) Your service book which has your compliance numbers - the bike is German so there is no problem here. The problems start if you don't have this book, so get it from whom ever you purchased it from. This can be in English.
3) You will need to go to one of the major border posts and import the vehicle. This involves turning up, showing your ID card and the bikes documentation. Customs will give you an import note.
4) Book into a testing centre, pay the fee and have the bike certified.
5) Arrange insurance. Budget around 1000chf for this as a first time registration. A word of caution here. Most insurance companies will take a five year contract, payable every year. This will often get you a cheaper deal, but you are fixed to that insurer for the term of the contract - none of this shopping around like you can do in the UK.
5) Hand over all your documentation and collect your new plates at the testing centre.
If you are not with a diplomatic mission or international org with tax free status, the major difference here is that you will need to pay tax and this could make a very sizable dent in the 30% saving. I am not sure if the rules have changed but you may be required to pay at least 7.5% on the new book price - so whatever it cost new in Chocolate land. This regulation may have eased as it has been a while since I did an import but being Swiss, you can guarantee that there will be a fee.
For your bike, you will need to show Km on the clock (most have Miles and Km so this should not be a problem) and you will also need to change your low beam headlamp for a right hand bias. Other than this, the bike is TUV so it will comply. Failure to comply may come if you have an aftermarket exhaust, funny little LED lights or something the testers feel is wierd (take off the TT metal headlight grill for instance). A stock bike in good condition should sail through as it's really just a standard MOT.
The alternative of course if to keep the UK plates and smile at the speed cameras, but you will probably have problems with your UK insurance (most only cover you for up to 90 days) and if the Swiss rozzers see the bike around too much they may start to look a little closer after three months.
There is a helpful book called 'Know it all Geneva' that has a section on vehicle import I believe - you should find this at your local Payot Book shop. Otherwise, the customs guys at the border are pretty helpful.
Good luck!