Use Fill Handle
1. Select the text that has the formatting that you want to copy
2. Move the mouse point over the lower-right corner of the cell until it appears as a black plus sign that is called Fill Handle
3. Drag the Fill Handle to a desired direction to apply the formatting to other cells
4. When you drag the Fill Handle, Excel intends to extend the series and the formatting. However, if you want Excel to fill only the formatting, click the AutoFill Options and then choose Fill Formatting Only
Copy without cell borders
1. Select the text that has the formatting that you want to copy
2. Press command + C (⌘C)
3. Click the destination cell
4. From the Ribbon, click Home tab go to Edit group and click the down arrow on the Paste button and choose Without Borders
