>>1225517Open GIMP, make a new canvas the size of your screen or whatever, open your image and duplicate the layer (on the side there's a layer window, right click the layer that's created when you load the image and duplicate it).
Select the layer on top, then move and resize the image the way you want. In the Filters tab, go to Light and Shadow and select Drop Shadow, and configure it the way you want.
Select the bottom layer and move it and resize it as well. It'll look like shit all zoomed in, so go to Filters, choose one of the blur options (I used Gaussian Blur) and play with it until you like how it looks.
When you use the Move tool you have an option to move entire layers, it's useful here. Solid color background is really simple, and for gradients you pick the two main colors (the foreground and background colors, by default they're black and white) and place it with your mouse and drag it. It's should be very similar with those other programs you mentioned.
