Best placed in June. It is circumpolar from most of the northern hemisphere, meaning it never sets and can be found on any clear night.
Cepheus is centred near right ascension 22.5 hours, declination +71°. It is circumpolar from most of the northern hemisphere, meaning it never sets and can be found on any clear night.
It reaches its highest point in the sky around local midnight in June, which is when it is easiest to pick out. Earlier in the year it rises before dawn; later, it is already setting in the evening.
SkyRef draws Cepheus in its real position for wherever you are, right now, along with the other 88 IAU figures.