To add to what Whopity says (which is 100% correct), although there is no legal requirement for a checkout, most clubs/schools will require one.
In this case, you must be sure to understand, before the flight, whether you are the captain (in which case the "instructor" is technically a passenger, you must obey the 90-day rule, he can not log the flight, and you log the flight as P1), or - more common - he is the captain (in which case you log PUT). In neither case is a signature required.
FFF
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