You can easily create a composition like this from three similar shots using layer masks in Photoshop. Basically, you set up a tripod, take a few single shots of you in different positions and compose the whole thing in Photoshop, using layers and masks…
First, select one of the shots as the main layer of the composition
open the second shot, select all (menu > select > all) and copy (menu > edit > copy)
paste (menu > edit > paste) into the first image, note the additional layer in the first image
create a layer mask by clicking on the marked icon in the layer palette
select the layer mask, choose a fairly large brush and paint with black ink in the mask, note how the bottom image reveals in the painted area – voila, that’s how layer masks work
finish the mask with a smaller brush for good detail. tip: use a brush with a softness that matches the softness of the image to make it look more realistic.
this image illustrates how the finished mask looks, you can activate this visual of a mask in the channels palette. Double click on the icon gives an option for color display and opacity of the mask
now you have the basics of working with Photoshop layer masks, we perfect your skills with a 3rd image, which you paste in the main document.
add a layer mask to the new layer, as before
with a little trick we can save some time and use the old mask from Layer 1 as a base for our new mask. hit the command key and click on the icon of layer mask #1, Photoshop will make an inverted selection of the mask. Invert the selection (menu > select > inverse) and fill (menu > edit > fill) with black ink, make sure Layer 2 mask is selected. see, half of the work is done already.
here again a visual of a half-finished mask
the mask view out of the channels palette
have some fun experimenting with layer masks – one can produce stunning results with a few images. Also, it is possible to use the gradient tool in a mask to blend 2 images, just give it a try!