We're often afraid of total creative freedom. Most of us, when presented with the opportunity of 'roaming free', default to going by the script, or not going at all.
No matter the type of creative pursuit, going by the book provides us with a shield, gives us protection from possible failure. Minimizes risk. Seemingly, abiding by the rules, even rules set by ourselves, strikes a balance between expression and safety. Nobody wants to trip, especially when others are watching.
Studies have shown that when we're improvising, our pre-frontal cortex, the part of our brain responsible for executive functions (planning, decision-making), significantly lowers its activity. When we 'roam free', our brain turns off its own control mechanisms.
If we, as humanity, would always be afraid of not going by the book, we'd never get to the point we're in. Copernicus would've never dared to question geocentrism. Da Vinci would've never explored new art ventures. MLK would've never delivered 'I Have A Dream'. (The speech, at least its finale, was improvised on the spot).
Open the floodgates. Flood your mind with novelty.