If you were to see a great gushing stream, and decide to stick your hand in it to push the water and make it flow better, what would happen?
Even as you moved your hand through the water, the water behind your hand would find it an obstacle to its direct progress. The water in front of your hand could go no faster because of the weight of water in front of it, and if anything would falter because your hand, the obstacle, is preventing the water behind it from steadily pushing it on.
You would be messing with the currents, messing with the flow. The same is true of creativity, but it is the hand of self-consciousness, of fear, of stress....we try to meddle with the creativity (whatever the form it might take, and I include simply responding to new situations in our daily life) because we are focused on the outcome, be that social or professional, or egotistical. In so doing, we obstruct exactly the creativity we want.
A person's health shows a similar phenomenon. 'Bad' health is easy to define in terms of injury, disease, illness, pathology. What is 'good' health? It is the absence of all those things, but a description of absence is not a description of the thing itself. Health is what we have already, we don't need to contrive it...when it is 'bad', it simply means there is something in conflict, something in the way of our natural state.
Too much preparation is often observed to be counter-productive. Again it is obstructing, it is trying to mould what cannot be moulded. Be yourself. Spontaneously. Your creativity is there, your job is not to mess with it - being honestly in the moment as much as possible, enjoying the wonderful flow, responding spontaneously from a place of far greater integrity.
Be yourself. (Everybody else is already taken).