Get Dogmeat and return to Sanctuary. Find the "You're Special!" book in the crib and use it. Drop it to the ground from your inventory. Tell Dogmeat to pick it up, but quickly collect it before he does so. If done correctly, he will drop the item and it will still be in your inventory (this can be done with any item to duplicate it). Pick up the copy Dogmeat dropped and to have two "You're Special" books. Drop both books on the ground and one should activate again. To get unlimited books to increase your stats as desired, drop the book and duplicate it. Drop both books and pick them up. Drop one book and duplicate it, drop all the books and pick them up, then repeat by dropping one book and duplicating it.