A.S.
I co-slept with my twins from the time they were about 3 months to 2 years. I didn't want anything traumatic for them, so we bought a bed and put it in their room and I would go to sleep with them there. I started leaving after they were sleeping and going to my room, when/if they woke up I'd go back. They are in kindergarten now and my one son is fantastic, goes to sleep on his own and sleeps through the night. My other one, I have to sit at the bottom of his bed for him to fall asleep (only takes 5 min.) and then he usually wakes at least once in the middle of the night and calls for me. Sometimes I have to sit with him and othertimes he'll go back to sleep. A lot depends on personality how it will go. I was not willing to make them cry it out or anything harsh. I have #3 on the way and this baby will sleep in a co-sleeper for a few months, but I plan to transition to a crib in my room at that time, then move the crib to his room.
Good luck!