So the creative juices just aren't flowing... What do you do?!
I look at other forums and designs, try and get some inspirations and maybe get some new brushes/vectors. It always helps if you leave the project for a while too!
I just shut it down and go to my silent walks. When I am alone the best inspirations come to me but it all depends on the person as some can draw inspiration from silence and nature while inspiration for some comes from society so the best to do when you're stuck is to stop and return when you feel for it.