At the moment is think that Syndra 
is a really fun champion to play.
pros: good cc good poke low cooldowns high burst damage she can throw Tibbers with her W :) epic fail to Annie
cons: mana hungry early game slow how do I play her well
Syndra requires high skill and i am not sure she is a great mage for s6
What r your thoughts and how do I play her effectively?
press R
She is deffinitely not on the strong side, if you want to play and easy burst mage you should go with 
or 
since their combo is pretty simple and they do a lot of damage and have good cc/ utility.
BUT, syndra is still a viable champion and she can definitely carry a game by herself is she gets ahead. I love Syndra even tought I play her less these days, I used to play her a lot and she is probably one of my most played champions.
To poke your enemy in lane, most of the time you want to use your Q everytime you can easily land it, and stun with your Q+E combo to proc thunderlord with and auto attack or W.
To proc your stun, there is 4 ways of doing it:
1- the most used, cast you Q and as the ball is forming use your E very quickly (basicaly press Q E very fast). The ball will fly where you casted your E and most of the time your enemy won't have time to dodge it if you time it well.
2- Use your E on an already present sphere, althought this require the enemy to be around the sphere so you can hit him with it
3- If your Q is on cooldown but you have an occasion to stun, you can use your W to reposition a sphere on the enemy and then use your E to stun.
4- use your E after you used your ultimate, resulting in an AOE stun. Even better with maxed E.
When you want to burst someone, always make sure you have some spheres around to max your ults damage potential. A good bursting combo is Q E W Q R. When you have more cooldown reduction you can try to add another Q in your combo to add even more damage!
I usualy build 
. Luden can definitely be switched for a 
, 
, 
or even 
if you want to. You can go 
if you want to cap the 45% cdr, pretty good in my opinion. If you are a little ahead, definitely get a 
. Syndra can stay safe and escape sticky situations with her E, and mejai will only help her snowball even more if you already are winning your lane. A Syndra with a fully stacked Mejai is probably GG.
Most of the time I find Syndra shining in the mid game, where she can deal great damage and CC in teamfights, and even 1 shot squishies. Later on, it's harder to one shot people since ADCs will probably get 
or 
if they find you too dangerous, and mages will get wich can totally cancel your ult, so it's probably not a good idea to use it on them unless you are sure it's down. But you can definitely make a lot of disruption in teamfights with your AOE stun and get some kills after you poked with your Q. ALWAYS stay in the back line, you are squishy, if they catch you it's the end. And you have the range to stay away from your enemies, so abuse that.
If one of your fellow squishies is getting jumped on, like your adc or any other squishy on your team, you can use your EQ to get the enemy off of him and turn the situation around since you and your ally will be able to damage the enemy while he is stunned.
If you are being chased, spam your Q to damage your enemy every now and then. Since it has no cast time you can use it while running, and most of the time the person chasing you will either abandon because they are getting too low from your kiting, or you will be able to kill them with a rotation of your spells.
A few combos
If you have a ball lying somewhere else, you can W it at the enemy champion, E, then Q, most likely they won't be expecting it. Q,E ofc A standard kill combo in lane would be Q, E, W and then Q them again and cast R while the ball is forming.
What I like to do sometimes I Q either on top; in front; or behind the enemy then E for an unexpected stun and of course if you need to reposition things then W
With a bit of luck she might get some help in the MYMU.
