In one sentence, describe what the following article is about:

This iPad-shaped icon appears in the upper-left side of the iTunes window a few seconds after connecting your iPad. Clicking it will open your iPad's page. If this is your first time connecting the iPad to this computer, you may be prompted to set up the iPad's preferences on this page before continuing. This section is in the middle of the page. It's near the top of the "Options" section. This will ensure that your iPad and your computer's iTunes can synchronize with each other over Wi-Fi as long as they are both on the same Wi-Fi network. This grey button is near the bottom-right corner of the iTunes window. Clicking it applies your changes. It's a blue button in the bottom-right corner of the iTunes window. You should now be able to connect to iTunes wirelessly whenever iTunes is open on your computer and your iPad is on the same network as your computer. For some iPad models, your iPad will need to be actively charging in order for it to appear in iTunes over Wi-Fi. This means that you can plug the iPad into a wall charger.

Summary:
Click the iPad icon. Scroll down to the "Options" section. Check the "Sync with this iPad over Wi-Fi" box. Click Apply. Click Done.