Well Here's my two cents:
Take the safety course first
before you can take a passenger you must have FULL CONTROL of your abilities.
That means learning to ride in all kinds of conditions, turning being very important because with a passenger it's alot harder.
When YOU feel ready try 2 up. Everybody has a different learning curve, it might take you until next season to feel comfortable.
That's OK better safe than sorry
Ride safe