Non-support Sona has a long history.

Every season Sona players will figure out a way to make her shine in anywhere but support.

from whom I remember: (Didn't get their authorization, will remove if they want)
top/mid Sona: Rapping Hipster (NA Challenger)
mid/adc Sona: A wild AP Sona / LuxSaysUmadGrin (Ajimu) (NA Challenger)
mid Sona: AP Sona
ADC Sona: Schuhbart (EUW Challenger)

and I played mid/top/ADC Sona.

Unluckily, due to recent changes by Riot· music company· takes away all fun · games, solo lane Sona is mostly gone in high elo.

So non-supp Sona is not too big of a deal. You are just learning new stuff.

In S9, Schuhbart and Calmskyy invented Sona and Taric bot. With klepto and let Taric farm, fasting Sona before finish supp item. When Sona finishes her supp item, she starts cs.

In S10, Schuhbart and Calmskyy invented Sona and Lux bot. With double supp item and split cs for 20 cs / 5 mins, which is more gold for both Sona and Lux to scale than the usual supp path without taking cs. Additionally, supp item itself is quite gold efficient. See video by The Tank Man: Play Video
And I've been playing double supp item ADC Sona described above since s10.

Even though Riot nerfed Sona and Lux, but double supp item bot lane with Sona still works well.

If you are below masters, abuse duo queue. Do not play this below masters if you are not duo queue.

(Patch 12.5, 3/10/2022)

Riot made it so that before 5 mins, you get about 5 cs / 5 mins or something, which is bad compared to just farm.

Start with tear and two pots, Sona can perma stack tear lvl 1 if you proc q aura on ally, getting about +40 free flat mana lvl 1.

And then cs till 5 mins. After 5 mins, if you are still laning 2v2, in which your supp is not roaming, then you can buy supp item (spellthief) and split cs with your supp.

in lane:
-you can perma stack tear with Sona q lvl 1
-lvl 1 is really weak, so ideally you don't want to trade beyond max range q, can sit under tower but stay in a range so that you don't lose xp.
-ward second bush before minions spawn, so you know if they will pull wave
-good luck csing
-good luck surviving

in teamfight:
-figure out what is most likely to kill you, avoid it
-can just aram after moonstone
-can roam if have gold punish thingie

Regarding control wards and pots:
-You don’t really need to buy more pots since starting item;
-Control wards is situational,
-Buying 100 control wards doesn’t win sona the game, but saving money and get moonstone & sofw will