101 things to do in a box?

This link should help you:http://www.clickertraining.com/node/167

It's great fun once the dog "gets it", and I used it in conjunction with some other exercises to cross my previously compulsion trained older dog over to the clicker.

First, get a clicker and a mountain of small food treats.
 
Second, charge your clicker.  Just click it and throw a treat to the dog.  He doesn't have to do anything, just click-treat, click-treat, click-treat lots of times.  If he looks up expectantly at the sound of the click, it means you're getting to where you want to be - he is linking the sound of the click with the prospect of a food treat.  Have a few sessions like this. 
 
Third, get a flattish box, or if you have a biggish one, cut the sides down a bit.  Get your clicker, your treats and your dog and wait.  Click the second  the dog does anything box related - always follow the click with a thrown treat.  Maybe it will just be moving or looking in the direction of the box at first.  When he figures out that X gets him a CT he will start offering it over and over - withold the CT and wait for him to escalate his efforts (Hey, what's going on, it worked before!)  Then CT for his increased effort, or for his attempt at something else box-related.
 
If you don't have a box you can use any other random object.  Maybe place a chair in the middle of the room to work with. 
 
Post back and let us know how you get on with it - it's a whole lot of fun and very satisfying when the dog "gets it", even though with dogs that have been trained with  other methods first there can be a slow and frustrating period where the dog simply waits for you to tell him what to do - that's fine, it's how training has always worked in the past.  The box game is a great way to get past that and teach the dog "OK, you don't have to wait for me to tell you any more, just Do Stuff and I'll let you know if I like it".

What a beautiful doggie. 

I don't have any suggestions on CT since I am only just starting myself - but having a puppy and training with C&T is a wonderful idea.  But I can add some insight on owning a working dog such as your Berner.  In addition to clicker training implement NILIF (google it) it is a great program and method, easy to follow, non physical and wonderful way to establish leadership.  In a few really short months you are going to have a large full size dog that is only a puppy.  Have your family follow the program it is easy and teaching them rules easily.

Learning to ignore bad behaviors (like jumping) now and rewarding good behaviors is going to be key for a large dog.  My dog at 5 months old checked my 5 year old into the wall and hurt his neck and shoulder.  He didn#%92t' mean it, he was just playing but that's how easy a large puppy can hurt a child.  Socialization is really important too, take him everywhere with you enroll in training classes and enjoy!  I hope you invested in a new car or big enough car?  River barely fits in the back of my SUV!