I use 1 AS quint, 2 ls, as marks, armor seals, cd glyphs (all flat, can mix a few scaling armor/cd if you like it better)
Start W, start Krogs. Smite as soon as it spawns, hit big once (to stun) switch to little till it will die from W burn, switch back to big (make sure leash leaves exp range before little dies or you won't hit 2 from camp)
Pop a potion/level Q on way to Brambleback. Hit Brambleback till he gets stunned (remember auto/Q/auto counts as 3 hits almost instantly,) switch to closer cinderling, attack till W burn will kill it, switch back to Brambleback, stun again, switch to 2nd cinderling, kill it, kill Brambleback. Pop 2nd potion.
Here you have a couple choices- gank mid, kill bird, kill grump, kill blue.
Easiest path- kill birds. Auto each little bird once, or twice if you're on 0/21/9 masteries (to trigger red burn on them) then switch to big one. W/red burn should kill little while you auto big one to death. You can smite when it comes back off cooldown if you want, thought I don't think it's needed (unless you got a bad leash.) From here, either recall/buy your smite upgrade or kill wolves.
Try to micromanage your autos for the rest of your jungle time, don't waste autos on stuff that will die from W burn, activate Q right after your auto lands for quick triple autos, try to move a little between autos for the melee camps (Krog, Brambleback, Blue, Wolves) to delay their attacks slightly if your attack+move is good.
For builds,
Defensive- remember Shy scales better with HP than armor/mr (she gets armor/mr passively from her R) so amount of damage you can take per hitpoint naturally goes up more than most champions as you level. But don't stack so much hp that you force enemy adc to make your life hell with a bork.
Offensive- she scales better with AS than AD (every single one of her skills scales with on-hit in some way or another)
For split pushing, don't be afraid to blow your ulti if you get caught out. It gives you some extra armor/mr as soon as you transform, and it's on a fairly low cd anyway. >40 autos away from having it again. If you really need to GTFO, walls are your friends, (unless it's a Vayne/Poppy/big Gnar chasing you.) Shy ulti can go over nearly any wall in the game, and even if they flash to follow, you'll do better in jungle area than most champions will anyway (can force them through your W burn path easier than in lane/brush juke with the small speed boost)
Late game she tends to fall off in power, so try to force a win earlier, unless you have a super late-game carry on your team that will be able to carry you through to the end. (EG: Nasus, Jax, Kayle, Lucian, Tristana) In those cases, become their personal bodyguard for the rest of the game past 35mins or so, and pray they know how to carry..
GL;HF, and Happy Birthday ;D