What does Hablamos mañana ya you voy a acostar que descances mean in English?

This is a bit of a mix-up! It looks like you're trying to combine two separate Spanish phrases:

* "Hablamos mañana ya" means "We'll talk tomorrow, okay?" or "Let's talk tomorrow, alright?". It's a casual way to say you'll speak with someone the next day.

* "Voy a acostar que descances" means "I'm going to bed. Rest well!" It's a way to say goodnight and wish someone a good night's sleep.

They don't fit together grammatically, but it's clear that you're expressing:

"We'll talk tomorrow, okay? I'm going to bed, rest well!"