Break the new ballet shoes in first, as darning can be more beneficial after the shoes are softened. Straight out of the box ballet slippers can be tight and different treatments can be used to make them more comfortable and improve the fit. Ballet shoes manufacturers sell salves and serums to help accelerate this process.
Remove the satin from the toe area of the ballet slippers by cutting out a small rectangle with a razor blade. Some dancers opt to leave the satin on the toes, before darning, but the satin will only get shredded with time and friction. For this reason, many ballet dancers remove it, as recommended by the article "Pointe Shoe Modifiers."
Double thread your needle with the embroidery floss and handstitch four sets of double row stitches straight across the toe area. A double row just means two parallel rows of stitching that are sewn close together. When finished, there should be eight handstitch lines, which will include four sets of double parallel stitches.
Join the double stitches using a slip knot embroidery stitch. Using the slip knot stitch will help to reinforce each double stitch, helping to make them sturdier. A slip knot stitch will encase the double stitches and make a knot with each individual stitch. Thus, each stitch starts at the bottom stitch line, going through two parallel stitches, before coming over to cover the stitches. Then as the thread loops around to make the next stitch, bring the needle through the loop to create a knot. Continue going behind, then over and knotting each stitch in the double row, until the end is reached. When finished, move on to the next row of double stitching.
Double stitch around the circumference of the toe box, and then reinforce these stitches with a slip knot stitch. Stitching around the edge of the toe will help make the area sturdier, and can also reinforce the stitches placed inside the toe box. Once these parameter double stitches are secured with the slip knot, join them to the closest double row inside the toe area, using the same slip knot stitch. These would be the top and bottom double row. Sewing the outer parameter double row to the inner double rows completes the darning process.