This Sona guide is recommended for ranked play, in which the support sits bot, does not cs, and heals and protects the carry of the team.

I use standard red mpen runes, as Sona has a strong early game with her passive and Q and you should abuse it every chance you get. Flat armor yellows are standard, especially when you are going up against another AD at bot. Flat CDR is extremely useful, as you need as much CDR as you can afford. I use gold/10 quints, as they are my prefered choice. I've done the math, and at the 20 minute mark, you earn 480 gold from just runes and masteries. I don't feel squishy without health runes, but if you do feel free to replace the gold quints.

You get Q first in order to have early harass and win your lane. After that you should be alternating between Q and W, and only taking a point in E at level 4 and 5, depending on if you know where the jungle is or not. I max E last because during the laning phase, you should never be too far from your tower, and there is a much more noticeable difference in maxing bot Q and W first. Also R takes precedence from any other skill.

Flash is needed as it has more utility than ghost, as you already have a built in speed boost on demand. You also need CV as the support of your team. It is on a 55 second CD, and thus you should be using it as often as possible. Early game you need to use it to keep track of the enemy jungle. Mid and Late game it is used to check bushes if you are in the enemy jungle and for vision of Buff and Dragon and Baron. At this point do not use it every chance you get, but keep CV for situations where you think the enemy is doing Drag or Baron and you don't have a ward (But there is no reason you shouldn't have a ward, except for maybe pink wards and oracles).

I always start with Faerie charm and multiple wards and pots. On my first trip back, I usually sell the pots I don't use, as my heal is usually enough to sustain me in lane. I build a quick Philo stone. My next item depends on how my laning phase is going. If I am winning the lane and think I am not too squishy, I will go for fast AP and get Kage Pick. If not get a HoG. Boots is the next item you should buy. Your tier 2 boots depends on the enemy team. If they are high in CC, Merc treads is the way to go, but if they don't have much CC, CDR boots is a viable pick. Sona benefits a lot from CDR late game. At this point, if my team is winning, and my W aura is enough to keep them tanky, then I will build a third Gold/5 item, and build a kindlegem. I can then build Shurelya's. The CDR and active are extremely useful. I like to move it to my 1 or 2 slot so I can press the active easier. It can be used either offensively or defensively. You can speed up your whole team to catch someone out of position, or speed your team to run away from a losing fight. If you are losing though, build Aegis, as it will help your teamfight tremendously, Then you should build either Banshees if you feel you are being focused and then Shurelya's. One of your late game items is a Deathcap, as it will give you more heal and poke.

All throughout the game you should be the one to buy the wards, along with your jungle. Do not let your carries waste their farm on buys wards. Everytime I go back I pick up at least 2, if I have enough gold. Endgame you should be buying Oracles to clear wards on key areas, such as baron and in your jungle.

As soon as you start the game, get Q and start charging your passive. CV their base around 7 seconds to see their items and where they will be heading. You can then plan you lanes accordingly. Protect your jungle, and head to bot lane before Blue spawns so you don't fall behind in EXP. Invade the enemies bottom bush and power chord and Q their carry. This should do a ton of damage and allow you to win the lane. Do not cs at all, unless you know your carry is going back or if you know the carry can't get to the minion, although this should never happen. You only need a point in E in level 4 or 5, depending on if you know where the jungle is or not. This allows you to buy two Gold/10 items and put off boots, but still get back to your tower quickly enough after you buy. You should never be low on mana while laning. Spam at will, but keep some mana in case you ever get ganked, as you Ult is a great deterrent for ganks. You should also be spamming all you skills in this kind of situation, with an emphasize on E and W if you are in danger.

During the laning phase, do not forget your passive can slow if proc'ed with E, and you should use this when you have someone ganking your lane. If you are against another AD carry and support bot, it is extremely important to have control of your brush. This prevents the other team from targeting you, and allows you to have greater control of the lane. You can also harass the other team easier, by exiting the brush, attacking, then retreating back into the brush. I sometimes put one ward in the brush with the other support, as this allows you to have more map control, and gives you carry a vision to target the squishy support if the game calls for it. Ward the brush to the river or even Drag around 4 minutes. This is the time junglers usually gank. However is there is a enemy Nunu or Shaco an early ward up the river is just as useful.

In teamfights, it is extremely vital that you survive almost the entire fight, as your auras are strong and underestimated. You should also be spamming whatever skills aren't on CD in a fight. Your Ult is another great thing about Sona. If you team initiates, hopefully with the tank, you can chain your stun, which will more than likely win you the team fight, if you team is half decent. You should practice on getting a good grasp as to how far the auras go, and then adjust your position to the team accordingly. Sona is a squishy support, and as such, should always be in the back. Your W and E are quite long range, and you should never be within melee distance of the other team.