Trans Lunar Injection = great success!
The most difficult aspect of this project was finding a stable orbit around the moon once the Apollo was within its sphere of influence.

If the TLI is accomplished using two separate rocket stages, the Apollo's velocity can be augmented once it is close enough to the moon. At that point you can 'fire rockets' and attempt to match the ideal velocity of the rocket to orbit the moon. The ideal velocity is a combination of the moon's velocity at the moment the orbit is to begin and the components of a stable orbit at that radius.

-Brian