Yesterday, I sold so many sandals! Previously, I had posted the products on my Facebook more times than usual. I know that letting customers view my products and answering their questions quickly is the best way to entice them to buy. However, I haven't done this yet to my satisfaction because I tend to become distracted by other things. We never say "quite many" because "many" is not something that can be scaled. It makes no sense to have "a little many", "much many", or "quite many". However, you can have "so many" or "so few". Notice that I said "is the best way" rather than "are the best ways" even though the two ways ought to be plural. You can use either one. I prefer "is" because it wraps up the two ways into one single method.

Yesterday, I sold quite a few sandals. Previously, I posted the products on my Facebook page/feed more times than normal. I know that letting customers have access to my products and answering them/their inquiries quickly are the best ways to get them to buy. However, I haven't done it well yet because I tend to spend time on other things.