it depends what kind of riding your into you could try erm
wheel walking
180 jump mounts then try unispins
learn to hop SIF (if you havnt already)
learn to ride 1 footed
erm
wrap around
bigger drops
you could try riding along a pole or something
i dont no… but there are so many things you could learn
i think you should start with various differ mounts
jump mounts, 180 mounts ect
rolling 180 twists off little drops
jumping off objects
1 foot riding
180 unispins when u get more cofident
then go on to wheel walking and other freestyle tricks
Basically deside what style of riding you want to adapt to and start learning trick for that
eg. if you want to ride street and stuff learn tricks that envolve flips n stuff
if u want to learn trials focus on hopping and fine balance and drops
and freesyle learn trick that envolve moving the unicycle in diffferent ways