I don't know what aircraft you fly. But when received "Cabin OK" you may also try one of these to be your reminder:
- switch video surveillance system monitor OFF;
- start timer;
- set wx radar tilt to positive angle;
- remove loadsheet (or maybe laminated piece of paper as suggested) which you placed in-between thrust levers before;
- start displaying MAP on your MFD;
- ...?
but nothing is perfect.
Or when lining-up ask yourself "Has she/he reported OK?" and when in doubt call to confirm...