A star rises about four minutes earlier every night — two hours a month, and a full turn over a year.
The Earth turns on its axis in 23h 56m 04s, not 24 hours. A solar day is longer because during one rotation the Earth has also moved about a degree along its orbit and must turn that bit further to bring the Sun back round. The stars are not chasing the Sun, so they keep the shorter day and gain 3m 56s on the clock every night. Over 365 days that is exactly one extra turn, which is why the sky repeats annually and why Orion is a winter evening object and a summer morning one.
It is four minutes of CLOCK time, not four minutes of extra darkness — sunset is moving too, and near the solstices it moves faster than the stars do, so a constellation can be higher at nightfall on successive evenings without rising any earlier relative to dusk. The figure is also a mean: the Sun keeps irregular time, and the equation of time swings the real gap by up to a quarter of an hour across the year.
Estimate with the rule, then check it against the calculator that models it properly.
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