Save the media you want to use or the photos you want to edit. Consider saving them all on your desktop or putting them all in a single folder for quick access. You will be able to open more than one image using online editors.
Open your web browser and open a free image editor (see Resources). These editors provide much of the same functionality as standard image editing programs, but instead of downloading anything, all of your editing is done inside your browser.
Choose the option to open a new file and select one of the images from your computer. If you want to open multiple images, click "File" then "Open" and select the other images you want to open. You can have multiple images open and switch between them at your leisure instead of having to work on one at a time.
Use the tools located on the toolbars and inside the menus to give your images the effects you desire. You can experiment with your image by creating a new layer. Look under the "Layers" tab to see your current image, right-click on it and click "Duplicate Layer." You can do any editing you want on this new layer, and if you do not like it, simply right-click on the duplicated layer and click "Delete layer." Your original image will remain untouched. To continue experimenting, duplicate the original again.
Save your image when you are done by clicking "File" then "Save." Save the image to your computer with the name and file extension of your choice. The most common are ".jpg," ".gif" and ".png," though ".png" is a popular extension as it keeps a relatively small file size while retaining much of the file's original quality.