backslide- use your back fool to grind and grab your leading foot

cheesgrater- practice bending your legs in positon before you try it, and practice like hell

unity- learn how to do the cheesegrater first, then swing your foot back around when you grind

tourqe- practice lots of backslides then just tweak your foot.

christ grind- only use one shoe, and place your foot on top of your shoe than practice with both shoes.

At first it was hard for me, but now it just comes naturally.