Shen is a really tanky champion on the team. He is extremely hard to burst down, even if its a 1v5. His shield is really useful if you are tanky. He is really useful in ganking lanes with his ult. If he has teleport, he can practically be at two places at once.

Pros:
-Useful shield, taunt, and global shield ult
-Can sustain in any lane
-Protecting people who carry
-Playing defensive

Cons:
-Basically no damage
-Easy to die when taunt on CD
-Vunerable to ganks

MID
Ok, so for mid I usually max out my shield because AP go mid and they can burst u down easily. Then max i max out my vorpal blade. Then my dash. If you are facing a Zed, who counters Shen. Do NOT max out your ult at all untill the very end. You can beat a Zed without your ult. Be careful about doing this since you have to tell your team you do not have your ult or else they will be pinging assist the entire teamfight or something.

TOP
Max out your shield, then your dash because they know you can't kite under the turret. The taunt will change that and you might even pick up the kill. Your vorpal blade last because it's not very useful on top lane except for poking. Shen dominates when kiting under tower. Which means free kills. Take flash and teleport

JUNGLE
This is hard for shen. I like shen jungling because of his taunt, ult, and teleport. Max out your vorpal blade for the heal, then your shield to sustain, then your taunt to gank. People say shen cannot jungle. I think shen can. His ult is useful against a trydemere because of tryn's ult. Take smite and teleport. Teleport to be practically two places at once.

When jungling as shen, u wanna do blue first for the CDR. Take your vorpal blade first. After blue, go straight to red because if you don't, you won't have blue and red when you gank. Get your shield second and your taunt last. After red, do the golems, then the wraths, then the wolves, then the wight. Many people forget about the wight. The wight is crucail to shen jungling because he needs to catch up to the laner's levels.

Shen excells at teamwork. Ult in when you see your teammate about to die. Do NOT use your ult on a teammate if you know they are going to die if you ult anyways. Let's say there was a 1v5. The 1 is your teammate. You would not ult because they will die anyways and if they last long enough you will end up teleporting there and kill yourself thus giving the enemy team a double kill. Ult when NECESSARY. Taunt the whole team if possible then shield right away to take off some damage from an enemy champion. If you have 40% CDR, you can be able to keep your shield up all the time, until you run out of energy. Throw your vorpal blade randomly i guess to an enemy champion and it will heal whoever is attacking that mark. At least your teammates.

I go tanky shen to that if a mid laner turret dives i can kite better, but AP shen is also the same but easier to die. AP Shen's ult is huge when its on ap. Same goes for his own shield. Tanky shen's shild is little but it still blocks the same amount of damage of AP shielf of shen's. His ult is better on AP than tankiness.

Well shen is a tanky and can kite very well. He has high sustain. I enjoy playing shen on all lanes, including bot lane (dont copy doing dat it messes up the team composition). Overall shen is weak, but he is fun when no one can burst you down (except for Zed and Teemo). If you enjoyed this build add me xtermin8. :D