I am entering this instructable into the Halloween Photo Editing Chalenge so if you like this then please vote for me! :D
Step 1: Getting the Terminator Pic
Step 2: Taking Your Own Photo
It's best to take a new photo as opposed to finding an old one that might work, this is mainly because few people have a terminator expression while posing for photos. You want to mimic the pose in the Photo of the terminator you are using, if you use the one I provided then this basically means a blank, expressionless face looking directly at the camera. Take a look at my ugly mug shot as reference if you need it!
Step 3: Putting the Picture Together
If you are unsure about what I was talking about then check out the pictures, they should (hopefully) clear up any confusion.
What this does is it uses the terminator image to form a new layer on top of the image of yourself, you can move this image about to center it if you want or you can just do it in the next step.
Step 4: Transforming the Image
Once you're comfortable with the opacity you'll need to right-click on the terminator pic and select free transform from the menu. this creates small boxes on in the corners ofthe picture that lets you drag and reshape the image as you see fit. To move the image just click and drag it into position. Reshaping is done by clicking and draging the corner boxes.
There's no real right or wrong in this step, you'll have to eyeball it. That said there are a few things to keep in mind; it works out best when you match up particular features between the two images, so for example try and reshape it such that the terminator eyes are over your own, the same goes for the mouth and jaw-line. Other than that it's determined by what looks apropriate. Once you're happy with it you'll have to confirm the transformation by selecting the move tool from the left hand side.
Step 5: Adding the Vector Mask
This creates a white rectangle next to the image in the layer menu, it should be all white. This box determines how much of the image is visible and how much is see through. Right now it's all white, so completely visible. If you selected the vector mask (by clicking on it :P ), select your brush tool and set your colour to black then you could draw over the terminator face and it would fade away. This would be very time consuming though and probably wouldn't give the best effect. Instead we'll use the gradient tool.
Step 6: Gradient
Now the fun begins! Once the vector mask is selected, click and drag between any two points on the terminator image. This causes the image to fade gradually between the two points where you dragged. Get a feel for the tool and have fun with it, but the main aim here is to get a fairly accurate fade between the torn off terminator face and the rest of Arnolds face. It doesn't have to be perfect, but the better job you do know, the easier it will be later.
Step 7: Touch Ups
I don't think it's possible to get it bang on right using just the gradient tool (if you manage it then well done!!!) so the next thing to do is touch it up using the paint brush. When you select the vector mask and use white, you will paint on the terminator face, when you use black you'll end up fading the terminator face and revealing your own. so you might be wondering to yourself "hmmm, I wonder what would happen if I painted on grey?". Well that is a fantastic question! the answer is that you'll paint on a partially see-through section of terminator face and this is very important for feathering the two images together and creating that seamless effect.
P.S: you're probably now wondering what would happen if you painted on red or blue or yellow or any other random colour. Well that's not as good a question, it does nothing of interest (I know, I've tried).
Step 8: Details!
After that what you should do is select the burn tool. to do this go to the left hand toolbox, right-click on the dodge tool (that'll look kinda like a lolly-pop :D ) and select the burn tool. Towards the top of the screen you'll see the burn tool settings, the settings I used are in one of the pictures; range set to shadows and exposure set to about 10%.
Remember, play around with these settings untill you're happy, don't be scared to experiment and save often.