when i concentrate on tucking i can get sidehops higher and easier. i was stuck on about 40 inch for ages, then i started to practice tucking more and have gone higher.. but anyway, sidehops are gay so dont bother there isnt really a technique for tucking. just imagine jumping on your feet but not bringing your legs up after you've left the floor. then if you pull your legs up your body doesnt go higher, but the distance between your feet and floor is bigger... hope that kinda makes sense?