The Code 777 cards have a diagram showing all the possible numbers in the game in the right color.
Diagrams are also printed on the notepad sheets. How to best use the Notepad is completely up to the players, since each player will want to take notes on the questions and their potential guesses in a different way.
However, as a general rule of thumb, you might consider using the Notepad as such:
In the Pyramid of numbers, scratch off any tiles you can see. You know you don't have any of the tiles you can see.
Also in the Pyramid, make a slightly different mark on the numbers that you think you don't have (or you have deduced that you don't have).
Since you may be making a guess here, you might want to know the difference between what you definitely saw on another rack and what you believe you know (or what you have reasoned by logic that you cannot have).
Use one Pyramid per shuffle of the tiles. When the tiles that were put out of play are brought back into play and shuffled to create a new draw pile, it is likely a good time to start using a new Pyramid.
On the new Pyramid, make sure to mark all of the tiles that you can see currently.
The numbers from 1 to 23 running down the left of the Notepad correspond to the 23 Question Cards, which are numbered from 1 to 23.
When another player asks and answers a question, you can make a small note next to the number of the question for later reference.
Just as with the Pyramids on the Notepad, you may also want to use a new column each time the tiles are reshuffled into a new draw pile, as the answers to the questions will change dramatically at that time.