  We present a new determination of the star-forming main sequence (MS),
obtained through stacking 100k K-band-selected galaxies in the far-IR Herschel
and James Clerk Maxwell Telescope (JCMT) imaging. By fitting the dust emission
curve to the stacked far-IR photometry, we derive the IR luminosities (LIR)
and, hence, star formation rates (SFR) out to z~7. The functional form of the
MS is found, with the linear SFR-M* relation that flattens at high stellar
masses and the normalization that increases exponentially with redshift. We
derive the corresponding redshift evolution of the specific star formation rate
(sSFR) and compare our findings with the recent literature. We find our MS to
be exhibiting slightly lower normalization at z<=2 and to flatten at larger
stellar masses at high redshifts. By deriving the relationship between the peak
dust temperature (Td) and redshift, where Td increases linearly from ~20K at
z=0.5 to ~50 K at z=6, we conclude that the apparent inconsistencies in the
shapes of the MS are most likely caused by the different dust temperatures
assumed when deriving SFRs in the absence of far-IR data. Finally, we
investigate the derived shape of the star-forming MS by simulating the time
evolution of the observed galaxy stellar mass function (GSMF). While the
simulated GSMF is in good agreement with the observed one, some inconsistencies
persist. In particular, we find the simulated GSMF to be somewhat
overpredicting the number density of low-mass galaxies at z>2.
