Choose now from the search results which image you like the best. click on it and it will be positioned on the custom sized area. Now track the angles of the image so that it has covered all the white space. If you wish so you can also put text on the image. You may want to give a name to that image so that you can find it easier after the download... click over the image where is written untitled design and give it a name. When you are happy with the result press download. Choose the format you need, JPG or PNG for websites.