This first one will require you to actually have two copies of the same photo - one in black and white and one in color. Use an exacto knife or small scissors to cut out the part of the photo you want to emphasize (in this one that would be my friends). Then put the pieces together and glue them to a piece of paper in a complementary color.
You can even do this process backwards if you want all your friends to look like ghosts.
This next one is not a thing I can really take credit for, since I saw a tutorial like this awhile ago on A Beautiful Mess. But I've been really wanting to try embroidering photos, so I did and I think it turned out pretty well.
One quick tip: you should either sketch out your design on both the front and the back, or just make a quick hole with your needle from the front side before stitching through the back, so that you don't bring your needle through in the wrong spot - with thicker photos like this one, it can be a little difficult to see exactly where you're going.
So that's all. Now I think I'm a sort-of black and white photo person.