There’s also lots of information here:
I would caution you about using plastic wrap though - I used to as well, but it allows most of the water vapour to escape right around the ANova PC - which is not what you want - the electronics at the top of the unit are quite sensitive to hot water vapour - often causing unpredictable results if you’re not careful. For any prolonged cooks, I’d definitely recommend a covered vessel with a hole that’s been cut for the PC (if the vessel is deep enough, then you don’t need to use your clamp - just use a hole saw and let the lid support the PC).