Hi my name is Snowrobokid and this is my first ever guide on Mobafire. So I'm here to help you build on my most favourite purchased support champion Sona.
Sona is a ap support which has 2 CC effects a slow and a really op stun. She is a great support since she has most of the things a support could do 1. Poke, 2. Heal, 3. Slow enemies and speed up team mates and 4. Stun for a long duration. Sona is a very good support since she has many passives to help her team mates with her music stances

Sona has everything you need to be a great support and my build is going to help your team even further.

APC - Ability Power Carry
ADC - Attack Damage Carry
CC - Crowd Control ( Like status effects like Slow, Stun Etc.)
CS - Minion Kills
AoE - Area of Effect
DoT - Damage over Time ( Burn effects like Ignite)
KS - Kill Steal

Pros

Op Stun
Great at poking
Can heal
Can slow and speed up
All her skills have a passive stance

Cons

Is squishy
Low ratio heal
Ultimate can be missed
Can Ks with her Q
Mana hungry

Initiating A Team Fight

When initiating a team fight when everyone there start off with your ultimate to inflict a heap of high damage done by your team after using your ultimate use your Hymn of Valor to do even more damage to them and your Song of Celerity to give your team mates a free kill or just ks with your Hymn of Valor when the enemies on low health.

Bad Situation in a team fight

When in a bad situation where everyone is nearly dead use your Shurelya's Reverie to escape or use your ultimate to let your friends attempt to kill them if not just keep spamming W and E to help everyone out. You can also use your Mikael's Crucible to heal one certain champion like a tank to go and initiate the fight and remember to use your ultimate if it's ready to help your tank out

Remember as a support never take your ADC's CS ( Unless they are recalling or are dead ). Also take items that you think that will benefit your entire team don't just take all all mana regen items thinking that it will benefit champions that don't mana instead having "Energy" or even champions that don't even have mana!
Also don't KS your team mates kills because we don't want them going toxic at us and the team. Only take kills when you're on your own and is handling a very low health champion.
Save supporting spells for champions that despretly