Are you counting each direction change? If so, you would have 300 possible combinations. If not, it's 75.
You need to add each consecutive number together to get the total. If you have 4 different layouts, then you need to also multiply the answer by 4.
12+11+10+9+8+7+6+5+4+3+2+1=75 | 75x4=300
Note: The above answer includes matching together 2 of the same fabrics (will look like a square of that fabric). If you don't want that option, get rid of the highest number.
11+10+9+8+7+6+5+4+3+2+1=63 | 63x4=252
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