Novice wheelie bin cleaner here.
I'm thinking:
Big squirt of washing-up liquid (or bleach?) to bottom of bin
Add kettle of boiling water
Leave for 30 minutes
Tip out into drain
More squirts of washing up liquid around sides and bottom of bin
Blast with hose but not too much as don't want bin to be too heavy to empty into drain
Repeat as necessary
Can anyone improve on this?