Brr, it’s been the perfect weather to play with yarn! Here’s a quick tip for casting on with two colors when your knitting project is stripey or otherwise needs two colors from the very beginning.
First, make a slip knot with both colors. Set up for the long tail cast-on but don’t make a long tail; about 4 inches is fine. Use the two colors instead of the tail and the ball yarn of one color. The strand you run around your thumb will be the base of the cast-on, and the strand around your finger will form the stitches on your needle.
Don’t count the slip knot as a stitch. Here are 5 stitches on the needle. My example yarns aren’t the same thickness, so that’s why the base looks so puffy. If you don’t want extra texture, stick with yarns that are the same type. Work the first row as specified in your pattern, and drop the slip knot off the end when you get to it. Very handy for patterns such as the Parallelogram Scarf or stranded colorwork that starts right at the edge!