Evaluate the needs of your students for the course. Organize the curriculum around a common special purpose, such as engineering or medicine. Consider typical daily communications such as memos or articles that the students will need to understand and produce.
Write out key objectives by which to measure a student's facility with English in their given need. Organize the objectives according to the order in which the students need to achieve each objective before proceeding to the next.
Develop an instructional plan of readings, assignments and activities designed to build the students' competencies in each key objective. For example, engineering students may read and re-write short procedural documents. Decide approximate time frames for each objective.
Formulate a plan for evaluating student progress. Keep the needs of the students in mind. Require students to demonstrate their facility in using English for their specific purposes. Write examinations or practicums that ask students to read, comprehend and reproduce communications that they will likely encounter.