Spiral plying supercoiled yarn gives you great texture...bubble yarn or ric rac
If you are having a hard time spinning a thick single to make a supercoil. Try using some of your corespun yarn. Corespun can be spun thick just by using a thick core, like mohair. Then you can easily supercoil this.
Some of my corespun supercooled.
Corespinning art yarn.
It is great fun to spin beehives and locks into your corespun yarn, If you are just learning to add beehives try using fiber from your batt, or matching fiber, your mistakes won't show.