Some people find it effective to have their own creative space. This may be a layout of a room in which they have music playing in the background. It could also be with respect to a certain layout of items on any work surface that they are familiar with, which helps them feel in control.
Others may feel it necessary to spend some time away from the problem, perhaps a walk by the beach or a form of fitness training can create the clarity of mind to create new ideas.
The way in which an individual sits or stands can have effect on creativity. Everyone seems to have a slightly different posture when they are at the peek of their creativity. For some it is worth remembering this position, in order to recall it when faced with a mental block.
This is a common problem that is occurred with in the creative world. People have the tendency to be creative for about 4 hours in any given day. So it is important that when a mental block occurs that the individual has the initiative to move on to some thing new. Perhaps make an updated presentation of new ideas, maybe attempt a different problem, creativity method or alternative project, but most importantly know when to take a well timed, clean break from the problem.