For anyone who never had done it before and have no idea, what kind of events follow before the ONS and in the bed. This audio gives a good reference what goes on in ONS.

https://www.youtube.com/embed/g-7oeBeqps8?start=505&end=2754.5

start time : 8:25

End Time : 45:55

Hope I haven't broken the piracy rule because it is available on youtube for free to listen.