I use PicMonkey to edit all my images. It lets me resize, crop, sharpen the image (like improving the focus) and more. For outfits, for example, I take the screenshots in CAS, crop them to be narrow, then create a blank canvas where I can set the width and height, and then add all the cropped images, moving them where I want them, and then saving the image. I also use it to "cut out" a shape that I can layer on top of another image - for example, make a heart cutout around an infant, and then add that to a full-size image.
I think all of these features are free - I do have a paid version because I wanted to be able to remove backgrounds, and that's behind the paywall.
Hope this helps!
