Sleeping Tips for LO

My LG is about to be a month old in 4 days. When she was first born she slept in her crib just fine. At 2 weeks she started only being able to sleep if she was being held or next to us in bed. I'm going back to work soon and I'm worried about her being able to sleep when I'm not home. I've started trying to transition her back to her crib. During the day I can put her down drowsy and she does just fine, but at night she basically demands to co-sleep. She gets a bath and bottle at 7:30, so that we're in bed by 9. The only times I have been successful at getting her to sleep in her crib at night is when she falls asleep in my arms first amd is fully asleep when we put her down. But she only sleeps for an hour when we do that. I might be on closing shift when I go back to work which wouldn't put me home until 11 or 12 at night. Any tips?