Hello-Through this forum I had the strength and patience to go through terrible biting by our collie tess-she is now nearly 6 months and although she will still 'mouth/nip' when excited she KNOWS she should not do it. At all times remain clam, turn your back and be still.
There is some wonderful advice given here-you must decide which you will adopt and stick to it.
We just have a whole shed load of other problems now like deficiency!!but the biting has stopped.