There are a few basic need-to-know items and suggestions that I can offer.
First: Bleach will not work on most synthetic fabrics. You will need natural fabrics. 50/50 Cotton and Polyester is best. 100% cotton will also work well, HOWEVER, bleach really weakens the material. If you get drips of bleach on 100% cotton, they will quickly develop into holes.
Second: I use Duralar material (.005) to create my stencils. Cardboard and paper will only soak up your bleach and become a mess. It is thin, plastic, and clear and you will get a lot of mileage out of each of the stencils you cut out of it.
Third: Cheap bleach is fine. It is still a toxic chemical. Wear a respirator or work in well ventilated areas, or both. Don’t wear anything you love. You’re spraying bleach.
With stenciling bleach onto dark fabrics, you have to think in the negative. This is opposite the general process of stencil work with spray paint or roll-on paints and inks. The light colors are going through the stencil and the dark areas are being blocked by it. Otherwise, this process is darned close to the spray paint stencils more commonly created.
For this stencil, I created the stencil for the half-tone layer to be applied first. On the back side of the stencil, I used a repositionable spray adhesive. This is a 3-M product and makes the stencil sticky but easily removable. It leaves no residue on the substrate (fabric). This is used to prevent under-spray for those clean, crisp lines and edges. It is important to also select a spray angle with your wrist position and stick to it. The angle of your spray should remain consistent throughout the even application. If you roll your wrist at all, you’ll risk under-spray and inconsistent application.
In this photo, you can see the shape of this stencil and compare it to the original drawing to see the areas I selected for the half-tone/lighter value layer. I also designed it to have a half-tone halo that fades into the background to enhance the outline. Spray this layer with the same, full-strength bleach but use a light mist for application. This mist will not be very wet. It is not to soak into the material. It is a fine mist that will lay atop the fabric and cause the effect. You will have to wait a few moments for the reaction. It will develop like a Polaroid. You can leave the stencil on for this effect in case you want to add a little more to make it lighter.
In this photo, you see me using some paper towel to pat the stencil. This is to prevent droplets and drips from the chemical that is beaded up on the stencil from dripping onto the fabric when the stencil is slowly peeled off.
The fourth photo shows this layer completed and fully developed.
In the fifth photo, the second stencil is applied. You will see a black marker line that is drawn on the reverse side of the stencil for alignment and registration. It is drawn on the back because the bleach will erase it from the front. I add the island stencil for the eye and it has also been sprayed with repositionable spray-adhesive. You can see in the first layer, I included a little line, that is actually sprayed as part of the design, for registration of this separate eye stencil. This whole layer gets the same, full-strength bleach. A heavier application is employed to achieve a lighter value. IMPORTANT: this is still not soaked. If you soak it, it will saturate the material and seep under your stencil. You will lose all your detail if you spray too heavily. Keep it consistent. You can leave the stencil in place until it develops to see if you want to apply more bleach to lighten it.
As with most stencil work, you will almost never get the stencil to properly re-register/re-align for a second attempt. This means you really can’t expect good results from trying to reapply the stencil for another attempt. Try your best to get each layer in one shot.
In the sixth photo, I am again blotting the stencil with dry paper towel to prevent drips and beaded chemical from running onto the material.
I cheat sometimes. In the seventh photograph, I am using a Sharpie fabric marker (this has dye instead of ink) to add three details; the nostril and two “V’ shaped lines in the tail.
This is the completed design. I used a black cotton napkin for this, instead of a tee shirt, so the photos in the tutorial would be clear.
You should know that when the bleach dries, it may crystallize. These tiny crystals are still dormant bleach. If these are re-hydrated, they can continue to bleach the fabric. I highly recommend running the finished piece in a dryer to beat these crystals out of the fabric before getting it wet by washing or whatever else. Be careful washing this with other clothing until it has been beaten and rinsed once.
Now, I know you may feel cheated that I did not disclose some amazing and secret technique but remember that I spent years experimenting with every other imaginable process and that this is the best, most effective, and easiest technique.