Masking in Photoshop to remove unwanted objects - when you have an image that is symmetrical or nearly so, and one side is perfect while the other is wrought with problems - duplicate the background and flip the layer horizontally.
To color match an image use the Match Color command. You will need 2 images, the source image and the the target image. First make sure you open both images in Photoshop, then activate the target image (the one you want to change), and go to Image > Adjustments > Match Color. In the dialog box, set the source file to the file you want to match. You can confine your color-matching to specific areas by creating selections in each image before you open the Match Color dialog box.
How to add clouds to an image in Photoshop - News & Musings - Photographer Photoshop Templates and Marketing Materials - EW Couture