There are 252 different ways.
formula is that, for words of n letters (not
palindromes, as in the case of the next puzzle), when grouped in this
manner, there are always 2(n+1) - 4
This does not allow diagonal readings, such as you
would get if you used instead such a word as DIGGING, where it would be
possible to pass from one G to another G by a diagonal step.