- Shen may not be a champion that you would play in jungle but he has a great clear (even on low levels) and especially in the mid and late game.
- Shen can make some really good ganks with his E and his ult ...the losing lane can become the winning lane just by casting your ult onto your AD carry in the 2v2 fight which can give you a free drake (or ganking your Top Lane resulting a free Herald).
-Depending on your rune pick your cooldown might be too long but it's not much of a necessary thing while playing him jungle (role that requires you to help your teammates by coming to their lane).

The first rune set "Base Runes" are proven to be the best runes you can take.
is a great rune for ganking and teamfights that grants you and your allies a bigger chance to burst your oponent before he can do anything, especially if you engage with your E .
give you a better jungle clear which is REALLY IMPORTANT! (and of course they give you some advantages later on when it comes to damage in temfights)

This part is pretty much self explanatory...
You should keep an eye on your minimap for 80% of the time and of course you should be aware of the allied champion icons (located above the minimap or on the left on your screen) so you can see if someone is getting low and gank him with you Ult .

-No matter what side of the map you play on you should always start at RED BUFF and then do the Krugs next because when killing Krugs for the first time in game they give you a -30% XP DEBUFF so killing them level 2 should result you having the upper hand next time you kill them.
-After clearing all the camps shown on the Image
https://ibb.co/SfhmpYK
You can:
1. Continue killing you other jungle camps
2. Gank Top lane (depends on the positioning of the opponent)
3. Gank Mid lane (also depends on the positioning of the enemy)
-After earning enough gold for the recommended First Back Items and of course the Oracle Lens Recall back to your base then start farming until you hit the level 6.
-When you get your level 6 pay a lot of the attention to your teammates in search for a good gank opportunity (your priority should be bot lane so after a successful gank you can take the Dragon)
-When you hit level 8 (or even level 7) you can clear Rift Herald by yourself.