When's the right time to ask for a recommendation letter?

I recently found myself in a bit of a pickle trying to figure out when to ask my teacher for a recommendation letter. I didn’t want to spring it on them last minute, but I also didn’t want to ask too early and seem pushy. After chatting with some friends, I learned it's best to ask about a month or two before the deadline. This gives your recommender enough time to write something meaningful without feeling rushed. Anyone else have tips on timing or maybe how to approach the ask?