newborn sleep routine

Chantal
Hi has anyone had success introducing a night routine with thier baby? My daughter is 4weeks old and at 3 weeks was sleeping 4-5 hours during the night. For the past week, she's been waking up at 3-3:30 and won't go back to sleep until 6:30-7:30. I'm wondering if there's anything I can do to encourage her to sleep longer.. anything helps. Thanks in advance!