If the text you pasted has a different style than text on the slide you pasted to, the Paste Options button appears. If the pasted item's formatting is what you want, the paste is complete. Otherwise, go to step 4.
If you select either of the above options and then decide you want the current design template styles applied, click Use Design Template Formatting (this is the default).
Note If you want to move an item instead of copy it, click Cut on the shortcut menu rather than Copy.
Tip
To copy, you can also press CTRL+C; to cut, you can press CTRL+X; to paste, you can press CTRL+V.