For the uni-spin don't try and land on the pedals aim for the cranks. They're a bigger target. Just throw your legs out and pull them back in as close to the wheel as possible. You can go for the pedals later on. Also for some reason I landed my first uni-spin after I lowered the seat for a friend of my brothers. It made it much easier.
to 1 ft ww... i suggest starting by ww and then just putting one foot on the frame. if you find yourself leaning forward, push really hard down on the wheel with your kicking foot. if you're leaning back too far, make very small kicks (or clamp your foot down hard on the wheel to stop it from moving completely until you get your weight centered again). sorry if that didn't quite make sense. tell me to elaborate if u didn't get any of it cuz those 2 things are the only things you need to know imo. balance left to right will come naturally.