Cleaning up your pattern and writing instructions is a step is often overlooked by those who don't share or sell their patterns. I personally always clean up my pattern and write instructions, even if I don't plan on making the pattern publicly available. Sometimes it can be months or even years before I return to a pattern. When that happens, I like to have a detailed set of instructions waiting for me so I don't have to guess what I was thinking. I also like to have a nice clean digital backup in case my original pattern is lost or destroyed. This is especially useful if you lose just one piece, you can quickly print just the piece you need. In addition, just because you aren't planning on sharing the pattern now doesn't mean you wont ever, so it's nice to have it done while everything is fresh in your mind.
I personally clean in my pattern in Photoshop CS6, though it is only one of many options available. For this guide I'm going to assume you have some knowledge of how to do this, but I'm going to walk through my own personal process.
To start, create a new file by navigating to File > New. From the presets menu, select U.S. Paper. This will create a canvas the correct size to print on 8.5x11 printer paper. (Of course, if you have a printer with a different format, you can select the correct size for your needs).
Once you have your new file, open your sketched pattern. Copy the image and paste it into your new file. Select the layer and reduce the Opacity to 20%.
Make a new layer on top of your image. Select the pen tool (P). You will be using this to trace over the lines of your pattern. There are many detailed pen tool guides out there, this is one of my favorites. To give a basic explanation, pick a starting area on one of your pieces that has a sharp angle to it, not a curve. Click once to start your path. Now click along your line. Clicking once will create a point that has sharp angles, but clicking and dragging slightly before releasing will give you a point with a curve. Dragging further away with your cursor will give you a rounder curve. To change a curved point to an angular one, you can use the Convert Point Tool under the same menu as the pen tool. Don't worry about getting the exact shape yet, just make a rough outline. Finally, click on your first point to join your path and complete it.
Here is my rough online.
You can see I've only placed points are major changes in the line direction.
The next step is to refine your path. (If you were automatically deselected when finishing, hold Ctrl and click on the path to go back to editing it). Click at any point along the path (with the path selected) to add a new point. Don't want that point? Click on it again to remove it. Hold Ctrl and click on any point, hold, and drag to move it. Each curved point will also have two "arms" on each side and you can drag to adjust those as well. They will change the way the line curves out from that point.
My technique is usually to put one point in the middle of the others and manipulate it to fit the curve. Sometimes I will need two if the line curves in two separate ways. If needed, I will adjust the points on the angles to increase or reduce them to match my pattern piece.
When your path is done, hit B to select the Brush tool. Right click and select a normal round brush. I prefer to set it to 7px with 100% hardness, but you can adjust the thickness as desired.
Now select the pen tool (p) again. Right click and select Stroke Path. A pop up will appear. Make sure to select Brush from the drop down menu and uncheck Simulate Pressure. Then hit okay.
The result is a nice, clean line. Now name your layer so you can keep track of it and make a new layer. Repeat this process with every piece of your pattern. You may need to arrange them to fit or make a new page if they won't all fit.
There are a few things to keep in mind here. First, you want to make sure the sides of your pieces match up. For me, I want to make sure my face patch will match the side of the head. Rather than try to re-draw it exactly, I will duplicate my body layer, erase the lines I don't need, and drag it to match the face patch piece. Then I will use the pen tool to draw the rest of the lines as normal. This may need a bit of erasing to keep it clean, but it will help your pattern's accuracy.
The next area of concern is with symmetrical pieces. You want to make sure both sides match up exactly. What I do here is generate only one side of the piece.
Now select the layer your lines are on and drop and drag it onto the icon that looks like a paper with a corner folded over on the bottom of your layers menu. Release to make a copy of your layer. Select the Move Tool (V), right click on the canvas, and select Flip Horizontal (or vertical if your piece is oriented that way). Then move the side into place. You may need to rotate it a bit if since your pattern piece may not be perfectly horizontal or vertical . Select both layers and right click in the layers menu, then select merge layers to join the two.
Once your whole pattern has been traced, the last step is to label everything.
First I go through and label any important connecting points. I make a dash with the brush tool and then use the text tool to assign it a letter. Labeling important points helps understand how the pattern fits together at a glance and also helps when writing instructions. Saying, "Sew from A to B," is easier than, "Sew from the point where the beak meet the face on top to the point where it meets at the bottom." I also make sure to label the eye and where pieces are placed in the body and include dashed lines for any places where top sewn detail will go.
Finally, I label the pattern pieces with their names, the color of the fabric, and cutting instructions. If your pattern is meant to be used with minky or any fabric where the direction of the nap matters, use arrows to mark that. Another thing I include is the fact that my patterns do not come with a built in seam allowance. For plush patterns, which have complex shapes, I prefer the pattern without it. You may also wish to mark where the openings will go for turning your pieces. I don't since I mark them in the instructions.
When it comes to cutting, don't assume that your audience (or you in the future) will remember that sometimes you have to reverse the piece. Be sure to write it when it needs to be done. Remember symmetrical pieces don't need this.
Now you have a nice, clean, finished pattern.
Next, I will go through how to write instructions for your new pattern and a few tips about communicating the steps and selling online.