To write a short sermon outline, start with an introduction telling your congregation what you are covering and why. Then, move on to the main body, where you summarize the sermon's main points. End with a conclusion that asks for a call to action and recaps the main points.
After writing out the main title of your sermon, write an introduction to your sermon that captures your audience. You can use humor, a news event or a relevant analogy to accomplish this, then find a scripture that captures the essence of the meaning behind the sermon.
Write out the main body of your sermon. Keep the body in an outline form with main points, followed by subpoints. Try to keep the sermon body down to three or four main points. The purpose of writing the sermon body in point form, and knowing the points well, is so that you engage with the congregation as opposed to reading off sheets of paper.
The conclusion of the sermon should recapture the meaning behind the sermon with an emphasis on the last point of the sermon. This is the most important point, as it is the one the congregation is most likely to remember.