While using “Sync” function you must not check the check box for “Brush” option in synchronize settings, as it may distort the image appearance. Even if the image is almost similar never check mark to this option.
To resize the image in Photoshop you have to go into menu bar, under menu bar you will find an option “Image Size”. On clicking that option, it will open a dialog box, by which you can adjust the size of the image.
Gaussian blur is a tool that blurs the edges of the image to make it more real and adaptive to the surrounding. Often it is believed that Gaussian blur can only blurs the image, but if it is used cleverly it will not blurs the image but enhance the appearance.