I have played Janna since i started with LoL kinda...ive played over 2k games now. Janna is my favorite champion because of her survability and she is epic in teamfights. She can beat a couple 1v1, maybe not xin but she have no problems at all running away from ANYONE!. Also Janna is very fun to play.

My masteries when i play with Clarity - Heal is like the ones above(8 1 21), i take 30 sec less cd on Heal then Utility for more cdr and the 3 % more movement speed.

If i use Clairvoyance - Heal i just change the clarity to Clairvoyance in my masteries...so its kinda the same.

Nothing much to explain ^^

i don´t know if i have to explain the runes i choose...But yeah, Movement speed quints is awesome because u dont rlly need any ap at start and the hp quints arnt that good.

Mana regen seals is my favorite runes at all mana champions i play, its good to be able to stay in the lane longer and so on.

Magic pen marks is better then ap marks and it isnt rlly any other marks thats good on Janna so yeah i choose magic pen.

Cooldown reduction Glyps i choose because i only get 1 item that gives Coooldown reduction, and who doesnt want cooldown reduction? :D

Core Build: Rabadons deathcap, Shurleyas reverie, boots of swiftness

All my games usually end before i get anything more than that, Because most games arnt that long...Otherwise i get Force of Nature for magic res and the 8 % mom speed and Lich bane for more ap and even more mom speed. (when u have all that no one is faster than you)

Last item i allways choose depending on the enemy team. I like Guradian Angel, its allways nice to have. But u can get another magic res item or a support item or whatever u want...

I Usually choose Clarity and Heal, Because its allways nice for both me and my laning partner.
But if i am laning with someone that doesnt use mana i pick Clairvoyance instead of clarity, Because Clairvoyance is an awesome support skill.

Dont use any other summoner spells because its no need for Janna. Like Ghost, Flash, Exhaust...Janna is faster then someone with ghost, she doesnt need flash to escape, she doesnt need exhaust because she alreaddy have a slow.

I start with Q to push at early game then i max my W skill first because it gives movement speed and it is jannas main dmg. After W i max E wich is my Shield. And i guess its pretty obvious why i max my shield skill before my Tornado...

Pros:
-Very fast almost unable to get ganked
-200+ ap so her shield is pretty good
-Decent armor/magic res
-Can stay in lane for VERY long
-Pretty good at ganking
Cons:
-No "Support" items
-Not much cdr

Save ur Ulti to save ur team or use it to heal them to keep on pushing. If a teamfight is close then save ur tornado to cancel ultis like katarina, galio, nunu, Malzahar have.
Use ur shield on ur ad carry at the start of the fight then use it at the one thats close to die. Dont use ur W skill in the teamfight, save it to escape/chase the enemy team down. Also remember when ur team is chasing the enemy team use Shurleyas reverie to give ur team more movement speed.

Also even if you do all the dmg at someone and your carry is close and can get the kill, give the kill to your carry, he/she needs it more than you.

If you play Janna good u can pretty much lane with anyone. When i play Janna i prefer to lane with someone that plays ad carry or tank. Janna is good at setting up kills for her team and her shield gives ad so thats why its best if she lanes with an ad carry.

If you dont see any teamfight coming up then go push a lane where no enemy is. Keep pushing untill you see one or 2 enemies comming close to you, because u can escape that easly. If they gank you, you usually get back alive and ur team get some free towers meanwhiles enemy team chase you, If they dont gank you, you can get down a turret then run to your team because its probably going to be a teamfight soon.

I dont play much ranked games...But ive played a few and most of them is with Janna. If you play Janna at ranked its very important to stay close to your team early game, because even if u can escape many ganks it isnt like normal game where u can play ad soraka and win 1v5...Janna in generall is very team based. If her team sucks then she cant do anything about it. I guess its the same with all support champions...

With my Janna build i have an early game advantage because i wont lose any lvls and can stay in lane forever....once i was in the same lane untill lvl 15 before first back, that game was very equal but very fun too :P.

U have huge movement speed u are faster then almost everyone, except maybe master yi with some phantom dancers, ulti and ghost. But your slow + airborne + ulti will help you get away from that. Also if u need more movement speed just use shurleyas reverie.

As i buy Force of nature and Guardian angel i have pretty decent armor/magic res so ur not that squishy that everyone thinks you are. That makes u able to 1v1 most ppl and if things turn out bad u can just escape =).

Farming in early game is important doesnt matter what champion you play. Some champions need to farm more some less. Janna doesnt rlly need to farm much early game if it goes good on her lane so she gets allot of kills/assists. Wich it usually do if you lane with a good tank or a good ad carry.

Mid game my farming is usually the rush to a lane without an enemy push the tower untill they come. Thats kinda the farming i do. Dont do it too often because your team cant win teamfights without you!