Do this first: verb + đã

At the very end of a sentence, đã means "first, before anything else": Để anh suy nghĩ đã. Let me think about it first. This isn't the đã you know before a verb, which says something happened. The place tells you which: before the verb it's the past, at the end it's "first".

It's often used to put something off for a moment, and goes well with để (let me): Để em uống ly cà phê đã. Let me have a coffee first. Khoan đã! is the set phrase for "Hold on!".

What comes next follows with rồi (then): Ăn cơm đã, rồi tính. Let's eat first, then we'll work it out. Rồi hãy says "and only then": Học xong đã rồi hãy đi chơi. Finish studying first, then go out. In Hà Nội the casual form is rồi hẵng. Saigon speakers often add cái before đã: Để em ăn cái đã.

Compare trước (before others): Anh ăn trước đi means "you go ahead and eat, before us". Đã puts one thing before the next thing you're going to do.