Some things I have tried as both a mummy and child care worker are;
*Rocking baby/toddler under a fan or tree to distract them from the fact that they are going to sleep.
* Have the radio on sofly.
* I hold Olive firmly and always cover her with either a blanket or put her in a sleeping bag. I shoosh and rock.
* I used to wrap her as a newborn and always think babies look naked without a wrap or blanket when they are little.
*Olive has pretty much always settled with boobie or now bottle but she also calms down when we take her into our bad and just hold her really firmly, shoosh her and pretend to go to sleep.
*Pretend to yawn and close my eyes.