You can use the services of a 'Customs Agency', you provide them with all the details, invoices etc. They provide you with a quotation of the import duties payable along with what I reckon is a very small fee for their work on your behalf.
You can then pay the calculated taxes beforehand or at the time of crossing, they ask for their fees to be paid beforehand of course. Yourself or whoever is transporting the goods can just get the paperwork stamped as you cross the border, they keep one copy if you pre-paid.
We used one company that is located right on the border crossing, they are used to dealing with imports of all, types and really helpful. As we are not far from the border we went there and asked a couple of companies in person. Use
www.local.ch and put 'Customs Agency and duty payments' in 'What' and the place or post code of preferably where the goods will cross the border. (Does not have to be but much easier if there is a query to deal with).
Would not bother with small value items, but once it is above a few thousand CHF then worth doings. Also proved useful when being stopped by German police/customs on our journey (think they were looking for smuggled goods).