It is very important to stick to this as varying from it will lose you marks.After you have completed your research you need to plan the structure of your essay.
These linking sentences should be provided throughout to give cohesion to your essay.
Therefore, instead of developing a thesis statement first, you may choose to read up on the assignment question and make notes on relevant concepts, theories, and studies.
Once you have these notes and can develop a summary of the issues, it should be much easier to write a thesis statement.
The main body of the essay should be structured with each paragraph being separate (but linked to the overall theme) and have your argument developing throughout.
In other words, each paragraph should focus on a different aspect of the topic under discussion but should also always be clearly identifiable as connected to the essay question.