Step One: Look into the innocent sleeping face of your adorable new kitten and worry that your grumpy older cat will eat him for breakfast.
Step Two: Keep your kitten close as the moment of truth draws near, savoring every minute of your time with this precious creature before all hell breaks loose.
Step Three: Feed the cats next to one another so that they get used to feeling happy when they're in proximity.
Step Four: Walk out of the room for a few minutes and come back to your fuzzball all sprawled out on your older cat like it's no big thing.
Step Five: Hold your breath.
Step Six: Let that smile start creeping in.
Step Seven: Bask in the reflected glory of best palship, and take plenty of pictures.