In writing a reflection on the Steinbeck novella, I think that you would want to pick areas of the work that "spoke" to you. Reflections work best when you are able to find that which intrigued you or stoked a reaction within you. It is from this point where it becomes easy to write about what you reflected upon because it is sincere and authentic. In writing about your voice in the literature, no one can do this other than you. What can be done is to find particular areas in the text where this reflection can take hold.
One of the most compelling themes in the novella that causes reflection is the statement made about dreams. The dream of owning a place is what drives Lennie and George and, later on, Candy. This dream is something that seems elusively close and then distances itself from the men as the narrative develops. The idea of broken dreams is also seen in characters like Crooks and Curley's wife. For Steinbeck, this broken vision of the American Dream is an area where personal reflection can be evident. Think about how your own dreams stack in comparison to what is seen in the characters. Reflection on what it must be like to come so very close to your dream only to see it dashed could be a point where some level of personal analysis and introspection is warranted. This makes for a very poignant reflection on Steinbeck's work.
The characters that Steinbeck develops are also worthy of reflection. When I teach this novella, a discussion point and reflection always comes out in Lennie's death. Lennie is so child- like and with such a good heart that it prompts discussion and reflection to see him meet with a brutal end. The way he trusts George and the way in which he simply wants to pet and tend to the rabbits is where reflection could be evident. The world seems out of reach for someone with so little in way of want. This can be an area where reflection can be generated.
Finally, I think that reflecting on whether or not George did the right thing is another area where introspection is rich. In assessing George's actions, much in way of personal thought and reflection can be demonstrated. George is charged with the most painful of duties in terms of being there for Lennie and having to kill him in order to save him. This might be a point where personal analysis can merge with what is happening in the text. Steinbeck's work speaks to the reader on so many levels. These are only a couple. Reflection can be found in whatever held meaning in the text and these areas possess some of the most meaningful elements in the text.