Create your first presentation in Keynote for iCloud
To create a presentation, you first choose a theme to use as a starting point. Each theme uses coordinated colors, fonts, and graphic elements for a unified look. Most themes also have placeholder elements like title text and images that you can replace with your own content.
In the presentation manager, click the Create Presentation button
in the toolbar.To create a standard-width presentation (with a 4:3 aspect ratio), choose “Standard (4:3)” from the pop-up menu in the top-right corner.
Note: If you’d like the ability to format table and chart data using the conventions of another language, choose a different language in the top-left corner before choosing a theme. See Create a presentation with the formatting of a different language.
Double-click a theme (to narrow the choices, click a category along the top).
Do any of the following:
Edit text: To edit placeholder text, double-click it, then type. To edit text you typed, select the text, then type. To format the selected text, in the Format
sidebar on the right, click the Style button near the top, then make your choices.Replace images: Select the image, click Image at the top of the Format
sidebar, then click Replace. Browse to find a new image, then double-click it.Add new text, shapes, charts, or other objects: Click an object button in the toolbar.
Add or delete slides: To add a slide, click the Add Slide button
at the bottom of the slide navigator. To delete a slide, select it in the slide navigator then press Delete.Undo or redo a change: Click the Undo button
or the Redo button 
in the toolbar.Enlarge (zoom in) or reduce (zoom out) your overall view of a slide: Click the Zoom pop-up menu in the toolbar, then choose an option.
Click the presentation’s current name at the top of the presentation, type a new name, then press Return (on a Mac) or Enter (on a Windows computer).
Keynote for iCloud automatically saves your changes as you work, so you don’t need to worry about saving your presentation manually.
To preview your presentation, click the Play button 
in the toolbar. By default, all new slides are set to advance on click (when you press the mouse button, Space bar, or an arrow key), but you can also choose to have slides advance automatically.
To close the presentation and return to the presentation manager, move the cursor over the presentation’s title at the top, then click the X that appears on the left side of the tab.