Here is a Instructable on making stencils, using photoshop even though I have a good amount of freehand in there too, just because I did not have time to make them in photoshop and needed to rush to get somewhat done for now.

Mother brain was done in photoshop so I could show you how to make images into stencils.
As for the rest of what you see has been done freehanded, "by drawing the shapes needed then cutting them out with scissors at that".

Things that are needed of course.....

-A image of a character or really anything you would like to use.

-Paint

-Exacto knife/ scissors [Yet scissors is hard to use]

-Printer and printer paper

-Photoshop [Unless your doing it all freehand] Only I don't really show you how to draw them.

-use your moms house walls so you don't have to mess up your own.;) You may want to get permission first.

-Use a paint mask for sure, if you are in a closed area, then things are going to get ugly. I forgot my mask.lol

Step 1: Find Your Image

For me I decided to go with mother brain.

Why, Because I wanted to do something retro and I feel that mother brain is by far one of my most favorite bosses on the super nintendo system.

Now that we got our image and opened it up in photoshop we can move onto the next thing.

Step 2: Selecting Our Subject

first use the lasso tool and circle mother brain , then right click the inside of the circle and make a cut to layer or just a copy to layer .

You should then have another layer appear at the bottom right hand corner of mother brain.
next step

Step 3: Editing Our Subject

Now turn off your last layer that you copied or cut from, it's going to be second from top in your layers panel.

Now you can go through and erase what background is left or leave it alone.

I chose to leave it because it all works out in the in for this image.

Next step

Step 4: Threshold Our Subject Sucka

Now we want to go to, at the top right...

Images , Adjustments , threshold and "click "..

You will get a window that pops up that looks like the one below.
Well, right in front of mother brains head sucka..

Move it to the left, NOW!
Until you end up with something close to what I have.
Maybe add a little more white so slide it a bit more one way or the other..

Next step, NOW!

Step 5: This Is Where I Skipped Erasing the BG.

My Background was not erased, either is yours you say?

Well, this is where everything goes black, then you realize you went into a coma. Not good at this point..

ok, back to mother brain...

We Invert our colors, it's better to print out black on paper then white. :)

Next step

Step 6: Fill in Black

Just make a new layer and use the brush with the color white to fill in any black spaces.

Step 7: Merge White Layer

Merge the white layer with the mother brain layer.

While on your stencil layer that is white, go to image, adjustments, hue/saturation.
Click on colorize and move last arrow to the right, that will make it black again.

Now make a new document the size of printer paper.
Photoshop should have a preset for it.

U.S paper is the preset, 8.5x 11..

Step 8: Resize Mother Brain for Printing

Now click and drag your mother brain stencil from the original file into the new printable paper size.

Press Ctrl+T to transform the stencil and make it big as you like.

Step 9: Sharpen

Now let's sharpen our stencil a little.

Go to

filter, sharpen, and use either,
Sharpen, unsharp mask, or sharpen edges.

Use which ever you think works best, what we are going for is a nice clean stencil.

Step 10: Cutting the Stencil

After you have printed your stencil, start cutting all the black out.

Here's a couple pictures to see what it looks like.

Make your slices/ strokes towards the black, because it's ok if you cut the black all up.
We just need to preserve the white space..

Step 11: Here's a Little Extra Stuff

Some stencils had to come in last minute.
Did not have computer or anything with me to make additional stencils so I had to go free hand with some..

But here is a couple of me making the lasers and circles, forgot to include the sketch of samus, Had to throw her in there last second as well.

I thought I was going to just make mother brain but you know how most art projects go, You want to start adding more and more.
You can't ever be satisfied with just one thing.
Also I was lacking colors, did not have the chance to get new colors but I may update this later when I have new results.

Step 12: This Is the Final Step

Tape up your stencils, anything lose in the middle you need to use something sticky like spray adhesive or in my case, a little soap just enough to get it to stick.

Don't over do that though, it may mess it up if not careful..

Have fun with your new stencils and hope that you guys picked up a new skill or something you enjoy.

Thanks for check this Instructable out..

Good Luck.