If you happen to be searching for images online make sure you can use them first. To do that click on search tools then usage rights and finally labeled for non-commercial re-use. If your wondering why you have to do this it's so that your not making any money from there images. After you have chosen an image visit the page the image is from, sometimes you can left click and it will take you straight there. Make sure the image has a creative commons licence so you can use it. The other thing you could look for is the attribution it should have the title, the author and the license information. You should now have full rights to use your image you wanted.
