Tacho entry after a year away from driving?!

As above, the correct answer is probably to use the question mark symbol up until your start time and then put other work from your start time until you put your card in.

Then your manual record comes into play when questioned if you have enough rest before starting. Officially this should be on tachograph paper or an analogue tachograph chart, but a diary is generally understood to be acceptable. Start and finish times only required.