  The amplitude and morphology of light curves of solar-like stars change
substantially with increasing rotation rate: brightness variations get
amplified and become more regular, which has so far not been explained. We
develop a modelling approach for calculating brightness variations of stars
with various rotation rates and use it to explain observed trends in stellar
photometric variability. We combine numerical simulations of magnetic Flux
Emergence And Transport (FEAT) with a model for stellar brightness variability
to calculate synthetic light curves of stars as observed by the Kepler
telescope. We compute the distribution of magnetic flux on the stellar surface
for various rotation rates and degrees of active-region nesting (i.e., the
tendency of active regions to emerge in the vicinity of recently emerged ones).
Using the resulting maps of the magnetic flux, we compute the rotational
variability of our simulated stellar light curves as a function of rotation
rate and nesting of magnetic features and compare our calculations to Kepler
observations. We show that both rotation rate and degree of nesting have a
strong impact on the amplitude and morphology of stellar light curves. In order
to explain the variability of the bulk of \K{} targets with known rotation
rates, we need to increase the degree of nesting to values much larger than on
the Sun. The suggested increase of nesting with the rotation rate can provide
clues to the flux emergence process for high levels of stellar activity.
