God luv ya!!! Congrats on the twins.. I dont know how mums who have multiple births do it!!
My little girl is 5 months old and self settles.
When it it sleep time I wrap her, give her a kiss on the cheek and a cuddle, tell her it is sleep time and put her in her cot. She will then go to sleep herself within aout 10 mins or so.
This is the only way I can think of to get them to sleep without rocking.
For the first few times they may have whinge or be a bit upset with the change of routine to get them to sleep but you will find they will get the hang of it quickly.
When I first started I let her whinge for a maximum 10 mins then went in to her but she never cried a upset cry more just a whinge. After a couple of goes she was fine and now barely whinges when I put her down.
You may find it works for you or doesnt just depends on what you are comfortable with. I started when hubby was home so that I had some moral support (she was only 5 weeks when i started so i needed it then! lol) and then once she was right i did it with all sleeps. she has slept through the night since 8 weeks and I think alot of it is because she can put herself back to sleep.