Does anyone care who is writing the guide? TL;DR I've been playing Janna main since 2012. All the way from her Season 2 Full AP meta when Rabadon's was a core item, til Season 6 where AP is unnecessary and Utility items rule the scene.

If I wrote a lengthy guide, it would be read by less than 1% of the players anyway. Janna is a high mechanical champ and obviously from what I or anyone writes is not going to help you too much, you are just going to need experience in the game and eventually you will start utilizing your own playstyle.

Janna is a very different support to conventional support. She isn't a tank, she is back line so she stands behind the ADC. This is actually very good because when someone comes in to poke the ADC or to trade, you just shield your ADC, and if they know what they're doing they will trade and then walk backwards, instantly winning the trade as the ADC took no damage. Save your Q for disengage only! Obviously use it in a teamfight though! Just don't harrass with it otherwise you will regret it when it's on cooldown and you have nothing to save your ADC with.

As I said, this will not be a lengthy guide. After learning the mechanics through your own playtime, here is 100% the way you get to High ELO.

You literally just stand behind and shield. And when you need an escape you run up closer, and throw a tornado in their face (or R if you really have to) and that's it. This is what I did all the way up to my ELO, obviously I know her mechanics well and yes that has helped me, but the basics of it is that this is how you play Janna. You don't need to tank, you don't need to harrass, you just protect and peel your ADC.

This requires fast thinking but you can win the game with plays like this. Against certain champions, let's use Vel'Koz as one. Miss Fortune as well, when they do their ultimate ability, you can flash forward and ult instantly and run away and it will push them to the side while also completely cancelling their ultimate ability. You can cheese champions so easily with this but you will need a lot of experience as Janna and how to play against other champions to expect it.

Wu Kong has a hard ultimate ability to cancel but it can be done, and if you do it your team will probably thank you. Keep an eye on Shyvana as well, she will ult with her dragon and if you are concentrating you can pop your ult and it will cancel her landing.

Stand behind your ADC. Shield him before he takes damage. Shield him when he goes in to poke. Disengage him with your Q when he is about to get destroyed.

Use your ult to heal and potentially make playmakers (Not recommended, you can **** up the fight so easily if you try make a play. Just stay safe and use it to heal and use it from a distance so you don't die while it is active. Remember it will NOT outheal enemy DPS at low levels. Hence why you stand off to the side to let the ADC get soaked in delicious healing winds while he kites)

Spellthiefs sucks compared to Talisman. Do your research if you don't believe me. A lot of players actually sell Spellthiefs mid-game to buy Talisman.

For the way I have constructed this build, telling you to stand backline and shield, think about it. If you are backline, why would you get spellthiefs? You aren't going to get any gold income because you aren't going to get any hits in. Having talisman is also a far better Active for Janna, as Janna's W already slows them. The movement speed buff is huge for escaping and getting kills and synergizes amazingly on Janna.

TL;DR Janna doesn't harrass enough to utilize Spellthief's properly, and also the fact that it's pointless on her because it's Season 6. You don't need AP/AD on a support anymore. There is literally no reason why you should be buying Spellthief's unless you are so low ELO that you need AP to carry. It's far better in this Season to buy items to help your ADC rather than be greedy and help yourself.