Hi
Okay. Firstly, hugs. This is a LONG reply - sorry. Hopefully you'll find something useful in here to help you. Sorry if not.
* So, a consistent wind-down is best. I go with simple and it sounds like you've got that covered.
* Experiment a little. See if making the room really dark helps. Make sure there's nothing stimulating around, no mobiles, no toys, nothing exciting.
* Try some background music or white noise. Quiet and constant in the background.
* Try using shhh patt to transition her into her cot. I've rambled on through shh patt below. Pick it up where you feel you and DD are now.... so if you think you can lay her down awake, then start at that point IYKWIM. Use the shh patt to help her move from your arms into her bed and into a deep sleep, without noticing because she will be so relaxed and focused on the shh patt. Oh, and may-be try just the shh or just the patt if you think it's too stimulating for her.
I started shh patt at 8 or 9 weeks when I discovered BW, thank GOD. Until then DS was a babe in arms and only slept on me, or by trickery. It got my LO off my chest and into his crib pn the first go so I am a massive fan. I think for some babies the combination of shh and patt can be too much (the closer they got to 3 months I found). This is what I did to get him off me and in that crib, and stay there:
* make that crib nice and cosy: I stuffed a couple of hand towels rolled up down the sides so it was soft and snug against his body. When he was really tiny I also took off the top I was wearing (so it smelled like what comforted him) and popped it in there too (side or underneath. A muslin that's spent a few hours under my top, tucked in my bra also worked well - folded and tucked along where a pillow would be. Great for spitups.... Oh, and a wheattie or heatpack or hot water bottle to warm up the bed just a little helped me too. Or put the blanket on a warm radiator first. Anything that would make you feel cosier if you were them, IYKWIM?
* find a rhythm that works for you both: the first time I tried shh patt it didn't work. I was shhhing like a banshee; loudly, too fast, too stressed to be relaxing and sounded panicky. Enter DH who (less stressed and tired) found a rhythm for us. My shhh sounds, to me, like water coming in over pebbles in the tide and back out again...so it's stronger in the middle and long. Then I got my pat rhythm too, I tried the tick tock tick tock (I'd used a heart beat rhythm previously and that worked well too). Very gentle pat on middle of upper back. I kept in my head what it was meant to simulate: womb noises, the wooshing of fluids and the tick tock of your heart. Your LO's used to that sound; comfort. You're recreating it. Not loud, not stressed, not panicked...just gentle and try to tune out if you know what I mean? Sounds unbelievably anal but over a count / beat of 8 (tick tock = 2), my shh lasted 6. Silence for 2 counts and then ssshing started again. The pat was constant. To keep calm, I tried to think back to the times I would pat my tummy gently (or rub) when DS was on the inside and had hick-ups. We had more success when I was in that mindset.
* swaddle. I think you posted that you swaddle already
* right then. shh patt him while holding him over your shoulder or, if you can, in a cradle position (less noticeable when LO's laid down). Keep it going: if screaming, be a little louder so LO can hear (but not so it's loud and scary) and quieter when they quiet down. As soon as you feel that lovely little body going a little more limp and floppy get ready for your move...and keep patting... and shhing...do not stop....now move them into the sleeping position still in your arms...still patting, shhing, still your warmth. Now start moving into the crib / bed, still spspspspsp. lay down gently and keep your face close to theirs (oddly warm breath near his cheek would often resettle my LO when being moved), once you've laid down, keep spspspsps. Hard so you might need to lay on side to reach back or start patting on chest (I found back hard after a while so I started patting chest before I laid down and continued in crib), keep it going but start easing off the volume and the pressure of the pat, slowing both gently. I did this until he was in a deep sleep. And sometimes he'd wake, and the SP would begin again (while still in crib whenever I could). Sometimes I'd fall asleep SP'g. Gradually (but as quick as you feel you can) start doing less and less of the sp to get them to sleep: so aim to get them in their bed, comfortable and ready for sleep. Initially, wait with them until you know they're in the deep sleep. When I was desparate for DS to get a really good sleep, I'd stay with him so that if he stirred after 30 or 45 mins, I could get him back to sleep very quickly and with little effort (often just the gentle pressure of a hand on his chest could be enough). Investing time early on pays off; leave the room too early when they're just in a light sleep and you could be doing it all over again...
*going down sleepy but awake: great to do this if you can. I couldn't initially. DH would put him in asleep, after a few mins of sleep in arms with SP (still SPg). I would put DS in as soon as I felt his head flop a little then get him to deep sleep in crib. Over the space of a week, I put him in the crib earlier and did less SP to get him to sleep. So...initially when his head flopped a little (just fallen asleep). Next time, just as head flops. Then just as body goes limp and relaxed but before the head flop... do you see what I mean. While in the bed, gradually do less SP to get them asleep. The shh pat is the means of you sneaking them into that bed without their noticing, IYKWIM
* keep an eye on the road ahead: where you are heading - to be able to take your baby and, after a wind-down, lay them in their bed awake and leave them to put themself to sleep. It may seem madness, but it's where you want to get to. So everything you do should be a move towards independent sleep (there are times you can't. AP with rocking etc can be necessary when you both need rest). Over time (a couple of naps, a few days, a week - depends on babe) SP slows and eases off so it's your hand on chest with a little gentle pressure. And then nothing at all
* cries whenever you lay him down: If you were in the cosiest place you can imagine, you'd be vocal when moved. You are warm, soft, smell like home and comfort and LO's world. Snuggled up with you is where they want to be more than anything so any move from this isn't really met with great joy. The aim is to get them so relaxed and focused on the sp that they don't really notice the move (helps if you're moving them somewhere warm!) and feel that you are still near (breath, warmth, pressure of patt initially). They don't know the bed is safe. But you do. Sounds obvious but in the frustrating sleep deprived hours I had to remind myself of that all the time to keep my sanity: babies are not rational.
My LO cried everytime put down for the first few days I think. And sometimes does now. If LO's distressed and upset, pick up and keep the sp going til they're relaxed again. And start the move again...frustrating, much? I tried to comfort in crib wherever possible, but sometimes it's not. Judge quickly the type of cry - a resettlable grizzle or an all out 'I need you' cry. I'd pick up if the latter and resettle with SP in arms; I'd try to resettle a grizzley cry in the crib but not always possible.
* OT: I have a rule that we still stick to now. If OT and the usual thing (SP or GW) isn't working, then we AP to get DS to sleep by whatever means necesarry. I had 3 options I knew: pram (didn't always work for me), car (90% success here) and my snuggled against my chest (was 100% now 5%! ). I'd pop him in the car first of all, check he was warm enough and drive. He woke if car stopped (rushhour was a 'mare), same with a pram. I would drive for hours if necessary around and around and around. Dual carriageways, ringroads, motorway...anything to get him asleep and see off the OT demons. The next nap we'd get back to that bed.
* If bed isn't LO's favourite place, try the afternoon nap somewhere else that they like so they get a break of scene before nighttime. I did the pram for the afternoon nap. Slept better with fresh air, helped me get out and feel a little more human.
* sadly, no advice on extending the nap in the car. My DS was the same. Would wake as soon as the pram or car would stop. Drove me bonkers.
It's a horrifically really long post and I'm sorry. Just trying to give you everything I can think of to help you. Be patient, be calm, find your rhythm.
HTH
Charlotte