Do you always have to do a manuel entry before each shift to say you was on rest period
As long as he consents, I don’t see the harm. Just don’t tell Sybil.
Benward09:
Do you always have to do a manuel entry before each shift to say you was on rest period
NO manual entry needed - unless appearing in faulty towers 
No your tacho accounts for activities at work. It’s not a diary of your life asking for what you did while away from work (ie resting)
Some like to present a complete record (those going abroad for example) but in the UK your lack of manual entry rest is covered by a ? which is unknown activity but presumed to be rest.