I think the most important thing in a lesson plan is to find out the goal of your lesson.
For example, if you want to teach imperatives, focus on what you want students to do after your lesson. You might want your students to listen to your imperatives and act out. So the goal can be listen to the imperatives, understand what they mean and act out.
Then you can logically plan the steps in order to reach the goal.
First of all, you need to recognize students' background knowledge, because it lets you know where to start.
If your students know stand up, and sit down, you might want to teach other things like raise your hands and so on. (the ones you want to teach.)
I hope this gives a little help. Everyone good luck!