Puzzled by your comment "... my blocks would be closer to 12 inches..."
Not exactly sure what you are asking, but before you cut your 3 or 4 inch strips, you need to lay the 6 pieces of fabric in a stack so the repeats are perfectly aligned. It's easier to do this with half the width.
Before you go any farther, do a search on OBW on this board. There is a tutorial that explains it all.