Hello there!

I main support and I just wanted to give some advice for your build. ^.^ I would definitely get Rylai's Crystal Scepter since that is an important item on him. I will say the Rabadon's Deathcap however isn't a good item for a support. Instead, I would replace that with a support item such as, Banner of Command, Zeke's Harbinger, or some tanky items like, Frozen Heart and Dead Man's Plate for armor and Abyssal Mask or Banshee's Veil for magic resist.

I wouldn't use Sunfire Aegis, Randuin's Omen, or Thornmail because enemies shouldn't be getting in your face. Your job is too peel and slow/stun the enemy for your team to pick them off easier. I also would try getting some sustain on Aurelion Sol because he does eat mana like no other. Getting Athene's Unholy Grail or Rod of Ages should definitely help and I would focus on getting a sustain item after you get Rylai's Crystal Scepter.

You also want to focus on placing wards which your build does not provide. Building Eye of the Watchers should help you a lot since it does provide Cooldown Reduction, AP, Health, Gold Income, and Vision. Simply start out by buying Spellthief's Edge and upgrade that to a Frostfang and buy a Sightstone. Then buy Eye of the Watchers for the remaining 550 gold.

Overall your guide is decent but definitely needs work. Sorry if I seemed a little too demanding and critical. :c

Good luck on your guide!

Well it's all a work in progress, I've yet to try every item combination. But I tend to take deathcap since the build is defense intensive and I find the additional 35% AP to be very helpful in terms of damage in the later part of the match. Four defense items really do improve survivability a great deal, not sure a fifth would be necessary, but it does come down to the situation. Sol tends to get focused alot by teams, because of the high threat he poses when allowed to simply work, that's the main reason for the build. Glad you liked the guide.

Hello, I'm a support main player, I just read your guide, and while I haven't personally yet tried Sol as a support I think there are some big flaws in your guide.
First of all I would max Q first, for the increased stun duration, as you'requested required to peel and help your team and you should be focusing on damage. Also a support should not farm, so the paragraph on farming looks pretty odd to me.
Finally, aside from rylai i would pick items that benefit my team better (Locket, Mikael, or Frozen Heart) definitely not Rabadon, unless we're snowballing hard and my adc isn't doing his job.
Anyways this is just my opinion, good job on the guide, I will definitely test Sol support soon, cheers!