You might know, you will get Unlimited Storage on new Google Photos. With the recent google Photos update you can easily edit your photos. This latest update having all basic edit options and few Advanced photo edit options.
First you need to click on the pencil icon found in the top right corner of the photo. It will be shown while you view a photo in full size.
After clicking Pencil edit icon, a lot of photo edit options will appear on the right side bar. This side bar categorized in three tabs named Basic adjustment, Color filters, Crop and Rotate.
Basic Adjustments Tab has Brightness correction tool, Color correction tool, contrast correction (Pop) tool, vignette option tool.
Color filter tab has Mars color filter, Phobos color filter, Deimos color filter, Ceres color filter, Juno color filter, saturn color filter, Mimas color filter, Rhea color filter, Dione color filter, Ariel color filter, Triton color filter, Venus color filter, Pluto color filter Eris color filter options.
Crop & Rotate tab has maintain aspect ratio icon, and rotate icon.
You can do all your edits and manually click Done icon found in the top menu. Or you can simply press right arrow key or left arrow key in keyboard, the changes you made will be automatically saved. Also Changes will be saved automatically when you click the right,left arrow icons over the photos. It will be showed once you hover the mouse over the photo. You can have the Revert back to original option too.