Sleep training / bottle feeding

My daughter we had on a strict routine since I went back to work at 2 months old. Daytime we keep it bright and loud! And playful. As we wind down for the day, we keep things a little darker and a little quieter. We start the nighttime routine by feeding usually around 7 pm. And then we'll play with her, do some tummy time as long as she has been up for an hour to avoid spitting up. We'll put her in her swing for a bit to kind of ease her (sometimes she cries for a bit, and we wait a little and then offer a binkie) to sleep and put in a pinkie. And then we do bath time which usually starts about 8:30. When we're done, we put lotion on and some nighttime balm, and I have booster pads in her diaper, because she's not big enough for over night ones yet. Meanwhile in her bedroom I have a humidifier and noise/light machine set to go on so it's calming. We'll get her dressed and take her in her room and I'll feed her while I play her some Mozart quietly. I don't look into her eyes much and I keep things boring.

I ran out of characters, I apologize it's so much to read. But I will say by the time she finishes feeding I keep her upright for at least 20-30 min and lay her down.
And we kept her on this and now at 3 months old she is sleeping through the night just great!

But obviously, every baby is different, I hope any of this helps

We do a variation of the chair method. I don't believe in any kind of crying out. We've had a routine since 7 weeks old though so it helps..
But we sit on the chair near his crib and put his paci back in every time he spits it out or it falls out cause that's what's comforting to him. It takes about 20 minutes but he falls asleep without needing to be rocked or soothed beyond that 90% of the time

Following

I work from home so I have had to be very stern with my routine. I started putting him on a routine at 6 weeks bc I noticed that he took to routines really well.
My nighttime routine is to keep the rooms dimly lit, I then wipe him down with hot water and a washcloth (I believe he is still too young for daily baths and the weather is still up and down). After, I put “lotion” on him. Put on his clothes and feed him (bottle). Then I will read him a book or have him look at his black and white cards. I then either rock him to sleep or just lay him in his crib and he goes to sleep.
I try to keep him up for 2-3 hours before bedtime.

Another part is making sure there are not too many naps. We do 3 naps for 2 hours. And it works VERY well.

He naps the same times every day. So much so he gets sleepy around those times and that means I don't have to rock him to sleep.

He gives me 8 hours (at least) a night, but his sweet spot is 10 hours. He's been sleeping like this for a month now.