How long would you shake your baby (< 10months) in the sarong/ yao-lan, to encourage her to sleep?

I wouldn't recommend a yaolan to lull baby to sleep, heard too many horror stories about injuries and suffocation. If it is still something you'd consider, I agree with one of the contributors above, not more than 30 minutes and keep a close eye on baby. Personally I would use a baby rocker or one of those bouncing chairs. I feel more assured that baby is in a chair like rocker as opposed to being enclosed in a cloth hammock.