DJs take used parts and mix and mash them up into something new.
DJs have a vast knowledge for music and can adapt to any audience. I have a friend that plays weddings and DJs raves, hip hop parties, and Latin parties, sometimes in the same day.
Creation comes from being a DJ first. Once you develop a good ear, you can graduate to build upon your own ideas. This is where the production or work comes in.
The best music producers also collect. The best writers read a lot. The best athletes mix and match skills and moves that made other players great.
Your best work is built upon the foundation of others before you, as you copy them to create your own unique style.
What type of DJ are you? Remember that DJing includes creating your own original work too.