Please help!!!!!

Jasmin • 21 , mother of a beautiful 2 year old little girl and now expecting another little baby 💕
So my daughter is gonna be 4 months on the 17th and never has she used her crib , i did the "mistake" of having her in my arms 24/7 and had her sleep with us as a newborn because im a first time mom and i was over worried at that point now im passed that stage and realize my daughter needs to sleep in her own crib i just dont know how to start! So im asking you ladies if any of you had this problem at first and how you fixed it ?!!