Planning is not necessarily easy for students and the difficulties encountered may be related to culture or general upbringing. Students are expected to be independent learners but some students find this difficult to start with because much of their life before university has been controlled by others. What to read, how to find evidence for the argument, even how to set out an essay are all things students have to learn, and at university level much of this learning has to be self-directed. This area of learning is often called study skills and these skills develop over time with practice and through trial and error. Study skills cannot be separated from essay writing; study skills complement essay writing.
There are many aspects to essay planning and it goes without saying that if you have two essays to write and they have the same deadlines, then the planning has to be done even more carefully.
Some important things to think about are time management, knowing what type of assignment is expected, the maximum number of words allowed, and knowing where to find books and articles that will help support your argument.