Your jacket or a piece of fabric large enough to hold the design you want
Acrylic paint, fabric paint, or screenprinting ink
Bright (preferably white) colored pencil or chalk
Iron (or hot pan)
Heat gun (or oven)
Sewing needles (optional)
Dental floss or thread (optional)
Scratch paper, pens, or something to sketch your design with
The hardest part. :) The following method can be done either directly onto the jacket or onto a separate piece of fabric sewn onto the jacket. In either scenario, make sure that you have a good flat surface. You may also want to clip or pin the fabric down to prevent it from moving. I use acrylics for all my painting, but you can also use fabric paints or screenprinting ink, available at many craft stores. Cheap fabric and acrylic paints can also be found at stores like Walmart. You don’t have to follow the below steps exactly. They’re just what has worked in my experience. If another method of painting is easier or more intuitive for you, do that.
Other methods can be viewed at the bottom. Also, if you’re copying an existing piece, some of the brainstorming advice below may not apply.
For brainstorming what I want on the back of a jacket, I usually pick 2-3 colors and 2-3 themes, experiences, items, or pieces of media that speak to me. I then think of what sort of symbolism might represent these, and how they could be combined. I’ll usually loosely scribble a few designs, often around 5, onto sticky notes to see how much I like them drawn out. I go back and forth on this for a while until I settle onto a concept I’m satisfied with.
From there, I take whatever concept doodle I like most and draw it out on a piece of paper in full. You’ll need this for reference later.
I then trace the design out onto the fabric with a colored pencil or piece of tailor’s chalk. You should have some basic line art now, and this is where it gets trickier. Think of your design as a paint-by-numbers page. Since you want the paint to have a black base coat, fill in the colored sections with black paint. Avoid painting over the lines you made with your pencil or chalk. Once the black paint has dried completely, add a white coat onto the black sections. Once the white has dried, paint over it with the final colors. You should have a fully colored piece that you will simply need to paint the lines around now.
To make things a little easier, you can also stage the process out by doing one set of colors at a time– if you have a piece with three red colors and two yellow colors, you could paint the black undercoat, the white, and then the red for the three red pieces, and then begin the black undercoat on up for the yellow. Mistakes and accidents are normal, so you may need to repaint over the lines or tweak some spots. For this purpose I suggest that your design have a very thick black outer border– that way you’ll be less worried about painting outside the lines somewhere where you won’t be able to paint over it to hide it.
You can also outline each black section in the color it’ll eventually be painted as a way to remind you what color goes where.
Once entirely painted, let it dry for at least 24 hours. Then, make sure to iron and heat seal your design. This will help set and preserve the paint. I iron the front and back of the fabric for 10 seconds over each area, making sure to protect the paint by putting something like a layer of cloth between it and the iron. Letting the iron touch the paint can cause discoloration. After that, I heat seal it by putting it in the oven for 5-15 minutes at 450 degrees Fahrenheit. You can also use a heat gun for this. I do not recommend using a hair dryer for heat sealing as it will not get hot enough.
If you're making the piece on a separate piece of fabric, you'll need to sew it on like a patch. I suggest checking out the patches page.
If you’re a digital artist, there’s an even easier method for a custom back available. Sites like Spoonflower allow you to upload your own design.
By doing this, you get a printed piece of fabric of whatever piece of artwork you’ve made and uploaded, which you can then cut out and sew on as a patch. I’ve done this before and it works fine. The easiest back design of all is to take a band t-shirt you like, cut the design out, and sew it on. You can also look for large back patches anywhere you’d look for other patches.
Depending on the area you’re in, you might want to avoid top & bottom rocker (semicircular) patches around your back patch. Plenty of bikers use these for their own designs, and while they might not take issue with yours, it’s probably wiser not to test that theory.