Before we begin, lets think a bit and prepare.

We need a minimum of two images, of two different people's faces, this is really up to you, if you want to you can have male/female, old/young, or something normal

Now, a few things you should keep in mind:
1. Make sure the two images have roughly the same resolution and are about the same size, this will make your final product much more realistic and accurate.
2. Make sure the two faces are looking in the same direction, it will look extremely awkward if you have one face looking to the right and try to implement a face looking downwards...
3. Always take proportion into consideration, you dont want tiny facial features on a huge head.

For this tutorial i decided to use Jessica Alba's face for the main person, and Carmen Electra's face for the actual facial features.

+ = ?
Click on these images for full resolution images.
Let's get on with it!

Step 1:
Load up your images, i first loaded up Jessica Alba, then loaded up Carmen Electra, and dragged her into the same document as Jessica Alba. To make things easier, please make sure that you name your layers!

Step 2:
Obviously we need to first look at proportion, we can clearly see that Electra's head is huge, covering Alba completely. So first of all we need to downsize Electra a bit. Go to Edit > Free Transform, Or just press CTRL+T. Now look at the top of your screen, we want to resize Electra's face to 55% of the original size, so we type in 55% and 55% for W: and H: respectively.
Press Enter, or click on the tick sign when you are done.

Step 3:
Now its time to position Electra's face so that it is facing the same way as that of Alba. To make our lives a little easier, we're going to drop the opacity of layer "carmen" to 50%.

With the carmen layer selected, we are going to free transform again. Go to Edit > Free Transform, Or just press CTRL+T. We want to rotate Electra's head so that it is tilted more, and looking at us more. We are going to change those values at the top again, but not the scale values, this time we will change the rotate value. Try 15'.

Perfect! You can see from here that their eyes are well lined up and so are the nose and mouth. Dont let the transparent face mess you up, trippy isnt it?

Step 4:
Before we start the whole cutting out business, we want Electra's face to sit on top of Alba's properly, so make sure that your move tool is selected (, press V), and make sure that the carmen layer is selected. Now drag it upwards untill everything fits perfectly together.

After we have our allignment correct, go ahead and put the opacity back up to 100%.

Step 5:
This is where all the fun begins! We need to make a selection of Electra's face, so select the Polygonal Lasso Tool(L), and start clicking around the peripheral of her face.

This should make a nice selection of her facial features. When you have created your selection, click on the Add Vector Mask button in your layers pallete. This one:

And that should cut out the face of Electra, and have it nested nicely on top of Alba's face.

Step 6:
Time to get rid of unnecesary edges from Electra's face! This is important: Make sure that the vector mask is selected on the carmen layer:
NOT
Notice the little box surrounding the mask, or thumbnail when selected.

Grab your brush tool(B), and get a nice large soft brush. Also make sure that you have black as your foreground colour.
Dewald's handy little tip: Press "D" on your keyboard to reset your colour pallete to default!
Now paint around the edge of Electra's face. Notice whats happening? No... its not an eraser! Its actually hiding the image where you paint, that means that where you paint black, the image will hide, and where you paint white, the image will re-apear! So if you make a mistake, you can quickly grab a white brush and make it come back! That also means that you can come back later and change the face again.

After a while, you should be presented with the lovely Jessica Electra!

Or if you're lucky enough you might get a Carmen Alba! (Even though she looks a little "sleepy" to me ).

I really hope that you enjoyed this tutorial, and hopefully you learned a thing or two from it. Please dont be shy to leave me a comment on what you think, or if you're stuck on something!

Attachments:

"Carmen-Alba" PSD	[Electra's head and Alba's face.]	2860 Kb	99 Downloads
"Jessica-Electra" PSD	[Alba's head and Electra's face.]	2143 Kb	66 Downloads