order of operations
 

OK, so I booked a flight for business. Do I go into the reservation and add legs now, or do I do this before purchase?

PenaltyCXL BY FLT DATE OR NOVALUE
NONREF/CHG100PLUSFAREDIF/


(I've never done this before, can you tell:D)

Depends on your tolerance for pain .. and change fees. ;)

General practice here is to book/buy the 'best available choice' the first time around, and be done with it.
If your carrier offers a 24-hour cancellation policy, you might be able to improve your itinerary with a fresh booking.

Good luck.
/.