Summarizing a presentation provides the opportunity to leave a lasting impression on the audience. The concluding remarks of a presentation are what usually sticks in the audience's head. At one level, the concluding remarks of a summary are like sound bites. They are short and condensed version of the the presentation. If someone missed the actual presentation and only heard the summary, they should have a good idea about the essence of the presentation.
Tell the audience that you are concluding the presentation. This sets the context for the summary and prepares the audience members for your concluding remarks.
Briefly summarize the primary points of the presentation. Avoid digressing into new information, arguments or points of view. Also avoid running a point into the ground that you have already discussed in detail during the presentation. The point of the summary is to remind the audience about the essential core of the presentation. Concentrate on the major ideas and the argument you made that supported the ideas..
Inform the audience about future work that you are interested in pursuing. The subject matter of a presentation usually has room for growth,development or elaboration. It is impossible to cover all of the bases in the time span of a presentation.
Conclude the summary be thanking the audience for listening. Tell the audience that you would be happy to respond to any questions they may having that relate to the presentation.