A reflective framework (sometimes called a model) can help you structure your reflection. Frameworks follow a step by step approach, with some including more steps than others. You can also use a framework to help you structure your essay. Students on some courses are advised to use a framework when writing their assignment. Check your brief for any mention of reflective frameworks and models.
There are many reflective frameworks to choose from. The University of Hull has a comprehensive guide on some of the most popular models. When selecting a framework, look at your brief, your word count, and the strengths and weaknesses of each model. You can also justify why you chose the model in the introduction to your essay. This evidences your critical thinking.