The steps for adding pictures to an already existing project, is similar to the steps outlined, with just a couple of details to take care of.

First, open the project you will adding pictures to. Then open the project "Presentation Macros" You can switch between projects in PowerPoint using the "Window" menu option. Click on the "Window" menu and you will see all the open projects in the list. Click on the project you want to add pictures to in order to make it the active project.

Move to the slide where you wish to begin adding pictures. Use PageDn or PageUp to move through the slides. To put pictures at the end of your presentation, move to the last slide.

Now press Alt-F8 to bring up the macro dialog box. Remember that the macros are in "Presentation macros." So you will need to tell PowerPoint this information. Click on the box labeled "Macro in:" and select "Presentation Macros" from the list.

Run the InsertPictures macro and follow the instructions as given in the previous instructional screen, up to the point where you are ready to click OK to add the pictures. Before you add the pictures, just make sure the check to "Create New Project" is off. This will tell the macro that you are wishing to add the pictures to the open project.