Now we need the slides to be mixed every time the file is opened, that is basically the shuffle macro has to be activated every time we open the presentation. To do this, go to the menu Tools → Customize... and in the Events tab under Open document press the button on the right Macro and search for the macro created, following the path byte.odp → Standard → shuffle followed by OK button.Save the document, close it completely and try to reopen it again. Now, pressing the F5 key to show the presentation the slides should appear in random order.Close the document (you will be asked to save, but it is not necessary to do it) and try to reopen the presentation again: the order in which the slides appear should be different to the previous time.You can use an empty template here or see the presentation shown during the Science Day at this link.