How do you guys create so many ads so fast?

Recently, a lot of people mention that the current ads meta requires testing a lot of creatives FAST.

Unfortunately, as a solo founder, this is very time consuming and I really cannot keep this up for long time.

I would like to know which processes / tricks you use to quickly test various different creatives - and I am not talking about changing a few words but entirely different asset styles both for video & images.