Basic theory:
To be creative is to have a divergent thinking pattern. If you are very logical then you have a convergent thinking pattern.
High amount of intelligence has a negative corelation with creativity. You should have average to above average intelligence in order to be creative.
Convergent thinking helps you to come to accurate conclusions if you have all the facts in hand. It will help you ask the exact right questions that you need to come to a conclusion. If there is ambiguity, there is a natural tendency to resolve the ambiguity before proceeding further. It is pretty binary. If there are 10 possibilities and 1 possibility is the right one then you think. Either the first possibility is the right one or the remaining 9 ones. So on and so forth till you get to the correct answer.
You also tend to be confident because you are consistent and past experience has reinforced your world views. You are focussed and plow through obstacles till you reach your goal.
Divergent thinking helps you to come to a wrong conclusion very quickly using only limited facts out of all the available facts. But this is a heuristic approach. You iterate and go off on tangents till you come to a unique solution which is ultimately correct after a long while and this process cannot be replicated. You get the answer first and the rationality of it later. You backtrack from the answer and add rationality to it later so it is logical and people around you, including you yourself can be convinced by it.
Basically, you aim for a goal and then go off on a tangent in a different direction. This different direction is a waste of time but you will learn something indirectly that will help you reach your main goal.
If you are logical, you use your intelligence in a conscious manner. If you are a creative type then you will let your unconscious brain guide you into a solution.
If you are the logical type and want to be creative, then the best way is to be obsessed about finding a solution. Do your best with your intelligence and then take a break. Like, go hiking, swimming or running etc. Then your unconscious mind will have a chance to come up with the solution and will give it to you.
People who are insanely creative know they are creative. There can be absolutely no doubt about it in their minds. People who are highly intelligent and logical don't know that they are intelligent without external feedback from their peers. They are just surprised as to why others are slow or have a difficulty in understanding something when it is so very blindingly obvious to them. They just "get it!" and have high cognitive processing speeds.