At Southwestern, we are given one to one supervision but you are in a room from day one (hey you have to get started sooner or later). Lectures on the basics are 4 times a week for three months plus weekly afternoon PBLD's, Q&A's, and simulator sessions for both basic and emergency skills. All are then shifted to advanced topics for the remainder of the year.
The senior residents function as mentors and if you are on an overnight call team, the call leader who is a senior resident, will provide you with more teaching. All in all I thought that I really began to feel comfortable by the second month. Lots of cases = lots of repetition and fewer mistakes as the year progressed.