bedtime routine help

Looking for some advice if possible...I have a 3 month old son and I kept reading/hearing that I should be establishing a night time routine for him. I've been trying for over a month now to get him into one, bath, cuddles, soft singing/lullabies, bed but he literally will not sleep unless he is ready and this can be 6pm or 11pm. No matter what I do if he isn't ready for bed he won't sleep and will scream the house down if I try to leave him to settle to the point he chokes on his cries. Should I abandon all attempts and wait a little longer or is there any tips anyone has to help. Thank you ladies.