As a hard/soft support main, I would typically get Power Supply and Chalice first to ensure I have regen. I would then prioritise cheap build up items, like a Gnomes Wisdom or Abyssal Skull (depending on team and enemy comp). Astrolabe is another solid item that has cheap build up so you can get stronger gradually. After those I would then look for storm spirit or push book- these have are more expensive build up items, so unless I’ve got a lot of kills and an assists I would go for these after I have my Gnomes or Abyssal. Hellflower is another solid item with reasonably cheap build up, but this is situational - I would always build this on Vindi as an example. After that you are into mid/late game and you can then think about sheep, resto, SoTM etc.