After you enter text, you can change it at any time. You can insert new text by clicking where you want to make the insertion and simply typing. Before you can change existing text, you have to select it by using the following techniques:
Select an individual word by double-clicking it. The word and the space following it are selected. Punctuation following a word is not selected.
Select adjacent words, lines, or paragraphs by dragging through them.
Alternatively, position the insertion point at the beginning of the text you want to select, hold down the Shift key, and either press an arrow key to select characters one at a time or click at the end of the text you want to select.
Select an entire slide title by clicking its slide icon ...