Step 1: Transfer the Image to the Fabric
Start with a simple line drawing/image (no shading). Print it out but try and keep it so that it would fit into a picture frame -unless you are doing a wall hanging- make sure you iron on a fabric stabilizer on the back. I used a light board to transfer the image to the fabric but fabric transfer paper also works well. Either way you need to draw over it with a white colored pencil or a fabric pencil so you can handle it and still have something there to sew.
edit: the stabilizer I used was the cheap Joann's stuff for $.99/yard. I can't find the brand because I think it was made by Joann's but Sulky Fuze and Stitch is pretty close. The fabric is 100% cotton quilting fabric. I chose black with scrolls so that the background wouldn't be too busy and take away focus from the knot.
Step 2: Outlines
Step 3: Filling in the Outlines
edit: ok I added another image from ms paint of the top and side views as well as the filling it. When filling in, I go around, from underneath up near the dotted line (the outline) and over to the other side and down. Again and again. The green picture is how its broken up. I start on one part, and about 2 inches away make a line, then I half it and half it again until everything is filled in completely. This way it doesn't seem like as much I have to do.
Step 4: Stabilizer Warning
Step 5: Finish Filling and Outline
edit: the outline:: this is your traditional embroidered line/curve. I've drawn in in ms paint for your viewing pleasure, now pretending that it's all black, I used multiple colors to highlight the actual stitches. A good way to start or improve your technique is to write you name is cursive, very large, and then embroider it. Ok now do your dog's name. Ok now find someone else's name. Keep doing it.
Step 6: The End
edit: I've added others I done in the same exact manner.