Around the circle of each Two Degree connection, draw 10 lines of about 2" and connect a circle to the end of it. These will be your Third degree connections.

As best you know at the current time, fill in as many circles as possible. It is fine to leave a circle black for now.

Since you had 50 Second degree connections, and each of those have 10 contacts, your Third degree connections total 500.

Your total is now 555.