Hello, this is my first build on League of Legends. Sona is one the the best support champion you can play as. I play her as an ap support carry on my team. One more thing, please excuse me for making grammar errors because I'm kinda poor on it.

Pros
best support champ
healer
pusher
mover
increase stats

Cons
squishy
most targeted in fights
low health

I choose these runes because ap for my spells, mana regen for my skills, mag pen to deal more dmg, and health to survive longer.

Pretty basic for a support champion, Clairvoyance and Flash.

Clairvoyance are used to search in bushes, show ganks, help chase down runners in jungle, check on areas of the enemy side of the jungle so your team can gank, and see if the opponents are doing dragon or baron.

Flash is to help you escape or get a kill on some1 or to use your ultimate to stop them running from your team.

The masteries are pretty basic. You might question me around y i didn't put more skill points in Intelligence. Well I have been playing around w/ it and found it more effective by doing that since max cooldown is 40%. 15+3+2=20 from masteries. 20% more from Morello's Evil Tome making it 40%.

Meki Pendant and hp pot = longer time in lane
Philosopher Stone = no more hp pots and higher mp regen
Tear of the Goddess = Mp regen to spam skill
Mercenary Shoes = More Mag Resist and Tenacity
ArchAngel Staff = Never to leave lane and spam all 3 skills in later game
Shurelya's Reverie = More Health, Regen, and Support Active
Morello's Evil Tome = Ap, Mp Regen, and most importantly Cdr
Rabadon's Deathcap = More Ap to kill and more healing
Abyssal Scepter = Ap and Mag Resist and Support Passive

The last item, Abyssal Scepter, is a good item. But some situation items are needed so replace abyssal scepter for something that is in ur benefit too.

Zhonya Hourglass = Dps like Xin and you get more ap
Banshee Veil = Mag Resist and Passive to counter heavy ap carry like Malz + u get more hp and mp
Thornmail = Dps carry like Yi
Void Staff = Penetrate Heavy Mag Tanks

Last hitting minions are kinda hard, but play several games w/ her so you no her dmg output so u can last hit minions correctly.

In the start, charge up ur passive so you can ur passive ready to go to harass. that way you do not need to use any mana for it.

Early game is when u have to use that passive to harass them so they cant farm properly and they have to keep going back to heal losing tons of exp.

This is where Sona will be the most useful. In team fights, you want to stay behind your tank or team because you will be most targeted because of support skills. You want to SPAM ALL of your skills because it will keep all the auras out for your team making them dominating with high stats. If your the carry of the team, make sure you use ur skill frequently and use ur passive to help conquer the fight.

This is how I play Sona. If ur complaining y it sucks, it is mainly for killing, healing, support, and sometimes carry the team. So go out there and try this build. Good Luck! And especially HAVE FUN