How can I build a series?

Make a shelf of books by age (first mazes at 4, picture mazes at 6, mixed mazes at 8, then weave, organic and extreme), by theme (pictures of animals, vehicles or holidays), or by name (an ABC book, or name books as personal gifts). No maze repeats across your maze books, so a second book from the same starting point never repeats the first. The same book can also be made in another of the 11 languages for Amazon's European stores.