If you have a corner or turn that makes it really awkward not to change direction, you can either color using curved lines or color using very small circles instead of lines. Just keep in mind that how you color will always be visible and will create the appearance of texture.
Embroidery Tinting with Crayons, Colored Pencils and Paint. When filling an area of embroidery, we usually think of fill stitches like the basic satin stitch or long and short stitch. Another way to add lots of color to your stitching, without lots of labor, is to use a technique known as embroidery tinting.