Tips for transitioning from bed sharing to crib?

*asking for a friend*

My friend’s baby just turned 8 months old and she breastfeeds and has bed share since her baby was born. Well now that her baby is 8 months and crawling she stresses about her daughter falling off the bed, suffocating etc. Her and her bf have tried transitioning her to a crib but she refuses to fall asleep in it and they are having a rough time.

My son is 7 months and has slept in a crib since he was born. She asks me for advice and I don’t really know what to say because I’ve never bed shared due to my own beliefs

For moms that have bed shared and transitioned to a crib, what did y’all to to smoothly transition? Trying to give my friend the best advice without sounding judgemental.