Nap help!!

My three month old will only nap on me and I’ve been trying to get her to nap in her crib! I wait about ten mins after she falls asleep then place her in crib, she immediately wakes up, Ive let her cry for 8 mins but that’s all I could handle then had to go in and pick her up. Any ideas or suggestions we’ve tried it for 3 days now and she just gets so worked up I spend 5-10 mins after just to calm her down only to have her fall asleep on me! Thanks!