Just as guys need to have a properly tied tie to make the best impression, a sloppy, lopsided bow will detract from that perfect dress you picked for your special occasion. To further the analogy, both require specific steps to create optimal results. But the rules are simple to learn, and the results are well worth the effort.
Hold the left strand of the bow in the left hand and right strand in the right.
Equal the sides of the bow. Hold both hands so that both strands are of equal length. Adjust if necessary.
Cross the left strand over the right strand and pull the former under the crossover of the two. Now the left strand should be in the right hand and the right strand in the left.
Fold the upper part of the strand that is now in your right hand into a loop so that the length of the loop is less than remainder of the strand. Hold the loop upright so that the remaining strand hangs from it.
Pull the other strand around the first strand from behind. Pull the middle of it through the hole created by the loop and create a second loop.
Pull the second loop until the knot is secure. Tug at the loose ends and the loops to adjust the lengths.
Adjust the knot if it is lopsided. In many cases, this can be resolved by pushing the part of the loose strands closest to the knot down so they fall under the loops on each side.
If you are able to slide the ribbon around the circumference of the dress, tie the bow in the front and then slide it to the back. If you are not able to do this, you will need a mirror and some practice. Try it out several times in the front before you attempt it backwards.