  Using the First Light And Reionisation Epoch Simulations (${\rm F{\small
LARES}}$), a suite of hydrodynamical simulations we explore the consequences of
a realistic model for star--dust geometry on the observed properties of
galaxies. We find that the UV attenuation declines rapidly from the central
regions of galaxies, and bright galaxies have spatially extended star formation
that suffers less obscuration than their fainter counterparts, demonstrating a
non-linear relationship between the UV luminosity and the UV attenuation,
giving a double power-law shape to the UVLF. Spatially distinct stellar
populations within galaxies experience a wide range of dust attenuation due to
variations in the dust optical depth along their line-of-sight; which can range
from completely dust obscured to being fully unobscured. The overall
attenuation curve of a galaxy is then a complex combination of various
lines-of-sight within the galaxy. We explore the manifestation of this effect
to study the reliability of line ratios to infer galaxy properties, in
particular the Balmer decrement and the BPT diagram. We find the Balmer
decrement predicted Balmer line attenuation to be higher (factor of $1$ to
$\gtrsim10$) than expected from commonly used attenuation curves. The observed
BPT line ratios deviate from their intrinsic values (median difference of 0.08
(0.02) and standard deviation of 0.2 (0.05) for log$_{10}$([N${\rm {\small
II}}$]$\lambda 6585/$H$_{\alpha}$) (log$_{10}$([O${\rm {\small III}}$]$\lambda
5008/$H$_{\beta}$)). Finally, we explore the variation in observed properties
(UV attenuation, UV slope and Balmer decrement) with viewing angle, finding
average differences of $\sim0.3$ magnitudes in the UV attenuation.
