Every individual today has different way or other route for approaching the process of their thinking. Poet Rudyard Kipling said he do have pure black ink into his pen before he could write. Immanuel Kant the philosopher always looked throughout his window at a stone tower to have bring back his thoughts, and he also said whenever there is obstruction to his view such like planted trees germinate and trying to cover or block his views, he chopped down the tree. That is to tell you that everyone has a way he views or pictures his or her thinking.
So many of this great people had way of doing their thinking. Another good example again, Composer Ludwig van Beethoven also have his own way of thinking by pouring cold water over his head to refresh himself and that help him to stimulate his thinking. Some many way other can stimulate their thinking even poet Friedrich von Schiller said his thinking can also be stimulated by the smell of rotten fruit (apple) he had kept on his desk.
But for me I don't think there is any specific things that trigger my thinking stimulation than closing my eyes and bringing in the view of the thought to my mind. Some many other people always find it or need music to trigger their Thinking also and whereas some do their best while operating computer. Some must write in longhand and it may differ from someone else but do whatever it takes and you probably believe it works for you.