Here are some examples of costumes I have made with sfx makeup. Sea Goddess, Zombies, Liara and Adjutant. The angry Demon brow was made using the mold made by the very talented Karin Olava Effects.
Photo: Sea Goddess and Liara - Nils Katla Photography, Adjutant and zombie Alice - Danarki, Death Elf - Artano Photography. Last zombie - Selfie.
The first and maybe easiest method must be liquid latex. Make sure that you use latex that is meant to be used on skin, and test on you hand if you are allergic to latex before you cover your face. I have also written a post about zombie techniques and tools earlier.
To make the paint more realistic my tip is always use at least 3 different colors.
To fix the teeth piece, I again cover my face with latex and tissue paper. Before tearing the hole for the mouth piece I put on my face paint. Note that Latex will show any face paint in a lighter tone than your skin. Attache the teeth piece with skin glue and add fake blood. You can either buy blood or make it yourself.
In addition you can make great effects with a bald cap, here I have glued on some random hair from an old with and hidden the edges with blood and bruises. And then we have guts ;) Here I have stuffed condoms with cotton and fake blood, but you can also find several tutorials online for other methods.
But there is so much more you can do with latex, for my sea goddess I used it to make tentacles and fins.
For the tentacles I used wadding around a wire then wrapped in plastic foil. Then they were dipped in latex. The suckers are cheerios dipped in latex. Latex glues to itself, so no additional glue needed. The tentacles are painted with grease based paint so it wont crack. To make them more shiny they are sprayed with fixing spray. You will find more info on the original tutorial here.
The fins are made with a cardboard skeleton which is painted with latex, which again is attached to my arm with tissue and latex. The white dots take focus away from the edges. More details are here on the original tutorial.
You can also cast latex, here I use Liara as an example. You will find more details on the original tutorial.
These are some tools I use when sculpting. The trick when you are going to make a mold is to not let the clay dry out, this way it is going to be easier to get out of the plaster mold. And even though I often use paper clay for smaller pieces, you should use oil based clay because it doesn't dry out in room temperature. for the scale patterns I just used the netting from fruit packaging.
Here are some progress photos of the sculpting.
To make the plaster mold I made it in several parts so it could taken off easily, which were glued together in the end. My mold is way to thin. You should make your molds 4 cm thick, so they don't crack.
To make the "hood" I slush cast latex, which means I pour in in the mold and move it around to make it cover every surface. You need to make many layers. Dry latex stick to itself very well, so remember to powder the hood while taking it out. More information on how to apply it and paint it you can find here.
And you should watch Emmabellish on youtube on how to put it on.
But now it is time for gelatin.
This is how to mix the gelatin, more information on the gelatin tutorial. When heating it up don't let it boil and don't stir it too much. This will create small bubbles that will then end up in the application. And also remember, this is a "fresh" application, keep it in your freezer until you are going to use it, and you should only use it once and make another for the next time you need it.
Here are a few short wip photos for how the Sea Goddess nose was made
Since I forgot to take photos of how I made the mold I'm borrowing a few photos from Instructables.com. The three problems I had was that I didn't heat it up enough the first time and it got really "grainy", and I got a huge air bubble because I didn't fill the mold enough. And lastly you need to press really hard to get thin edges. Also do not use latex to blend a gelatin piece, because the color will be different on the different materials.
Here are a few photos to illustrate the difference between water based and grease based makeup. Water based is easy to apply with both brush and sponge, and easy to make detailed patterns. It is also really easy to wash off. But you can't use it on latex since it will crack.
Grease based sits much better on latex and gelatin, but you need makeup remover to get it off your skin. it also blends better to your skin and doesn't crack. You should seal grease paint with transparent powder and fixing spray, so it doesn't smudge off.
And speaking of makeup tools. Here is a photo of transparent powder, fixing spray and two different skin glues.
Transparent powder is used to set the makeup and will not dull down the color.
Fixing spray makes sure your makeup hold the entire con and doesn't rub off.
Mastix is a very strong skin glue, but smells very strongly.
Pros Aide does not smell so much and will stay "tacky" a while so it is easier to readjust you prosthetic.
Lastly I will show you a video of my putting on my Adjutant makeup, which took about one and a half hours.