Here are some tips for writing TOEFL from the website:

  • Don’t waste precious time obsessing over introductions and conclusions, keep them brief and focus mainly on your body paragraphs
  • Devote a small amount of time to brainstorm and plan your essay, 3-5 minutes maximum
  • Remember that in addition to details and examples, you will also be graded on organization and coherence
  • Practice at home by doing quick five minute outlines of TOEFL writing topics

Here is a great video about brainstorming for the writing question before you write it. This will help you to write coherently and in an organized manner:

The following link will also give some advice for brainstorming and writing for TOEFL.