All the instruments, melodies and arrangements have been 100% made by the producer. No free-royalty use loops have been used to create any part of the instrumental of this track. There can only be loops only in the drums section (claps, shakers, top loops, etc) and ambient or vocal samples as a support of the production arrangement.
I usually start my beats with my instrumentals, and try to find a really nice drum groove for it. Then i make a bass (normally use Sylenth1 or SubboomBass vst) that conversate with the groove. But, of course the process is variable.