Looking busy for your manager is a skill. Being useful is a better one, and it’s easier to keep up.

Performing effort takes continuous attention and produces nothing that lasts. You have to watch where the manager is, keep the right things visible, and sustain it for the whole shift, which is genuinely tiring. Being useful costs about the same energy, leaves something behind, and stops needing an audience.

Pick the thing on your shift that would actually help if it were done, and do that instead of arranging your visibility. Tell your manager it is finished rather than hoping it was noticed. Over a few weeks it is also the easier way to work.