My Favorite Brainstorming Technique

Last Friday we were doing a Brainstorming techniques to learn how to make a writing. 
At First, the theacher puts on the blackboard 5 topics and we had to choose one of them, so i chose festivals.
Next we started to do the Brainstorming techniques which were:

-Making a list: In this technique we had to make a list of several topics related to the main topic that it was Traditional festivals in Murcia. For instance, i wrote the side of garden, the burial of the sardine and the moors and chrisitans. I usually use this technique in many exams when i don´t know what i have to put on them. If the teacher gives me a piece of paper, i make a list of all the ideas that are happening to me and that are related to the main topic.

-Mapping: In this technique we had to put the main topic in the centre and the other items that i had written in the previous technique around it and then we surround them with a circle. After that we connected them with lines. Later, i got more ideas into each subtopics. Finally i realized that many words had a relationship with the main topic. 

- Freewriting: This technique was the last one that we did in which we had to put the main topic and write down everything that occurs to us related to the topic. 
This latter is my favorite technique because i can write everything that i think without paying attention to spelling, grammar,etc. From my point of view i think that this is the most appropriate to improve fluency in English. I always use this one to practice for an writing exam and especially for an oral exam. 

In conclusion i think that the best technique to make a writing is freewriting. 
At first i thought that this was a nonsense, but then i realized that practice it had a lot of advantages and with this technique is almost impossible that your mind goes blank.