Establish a web-platform that allows you to communicate with students by holding video conferences, web calls, live chats and forum conversations. The more ways you can discuss grammar the more likely your students will grasp complex concepts.
Divide your regular lesson plans into three or four activities that last five minutes to 30 minutes. For example, if the lesson is about the subject and predicate, the first block of activity would be about definitions, the second about examples and the third about practice. Make sure that there is at least one hands-on activity to keep students engaged.
Review the definition of key terms. Build an online vocabulary list with definitions and examples to help students while they study.
Use concrete examples to demonstrate each grammatical concept. For example, provide text and video clips of Shakespearean plays when teaching students about rhythm and iambic pentameter.
Give students immediate feedback. Provide students with an answer key or automatic grader for every online activity. Providing students immediate correction will help eliminate the repetition of mistakes.
Keep the lines of communication open between students and yourself. Monitor discussions, and allow students the ability to discuss other subjects freely -- any written communication is an exercise in use of grammar. Permit students to ask you questions. Answer questions and provide clarification in forums where all students can benefit from your responses.
Evaluate the performance of your online classroom based on student reviews and grades. Adjust the teaching environment to suit your students' needs. For example, if your students are progressing but never attend web seminars, eliminate this activity and turn your attention towards another area.
Refresh class activities continually to keep students from getting bored and wandering to other websites.