I am so glad you asked! The majority of stockings that I make are from a company called Bucilla - you can read an excellent article on there here.
A general rule of thumb of these kits are they are comprised of pre-stamped felt, cotton embroidery floss, sequins, beads, stuffing, and many times splashes (for lack of a better term) bling or change up's from the original kit design.
Experienced sewers will sometimes change the color of a design, change the pattern lay out of a design. Check out this awesome example of the kit "Snowman Kisses" by Bucilla. The crafter has (original is on the left) created the first stocking as indicated in the kit instructions with the felt provided. The altered Snowman Kisses stocking (on the right) has had the snowman's scarf and the child's dress changed to a deep burgundy felt which has been paired with complimentary muted green tones in contrast to the original design.
Sometimes though, changes can get a little cray-cray! I have seen some Bucilla Stockings that no longer resembled the original design, at all! So, in this crafter's opinion, if you want to change them up a bit - DOOOO IIITTTTTT!! Would I change them up and add 5lbs of sequins and leave no redeeming qualities of the stocking? Not so much!
Check out my handmade felt christmas stockings for sale