Twist of lolita...
Ruuzusokkusu were in fashion in late 1990's among Japanese high school girls. Initially, they were wearing their modified version of thick mountain climbing socks that they stretched out to be loose.
After the popularity took off, the product “loose socks” (ready to be worn loosely) appeared on the shop shelf. ルーズソックス
Cut the sleeves off your sweatshirt along the armpit seam.Cut off excess fabric-remember,that both ruuzusokkusus have to be same lenght.
Hem the bottom of both your ruuzusokkusus...voila!
Now put on your creations-the elastic wristband should be just under your knee.