Como dizer "Prepare-se para" em inglês

"Get ready" é a expressão mais geral para dizer "prepare-se" - e é a minha sugestão. "Brace yourself" é usado no sentido de se preparar para algo ruim, difícil, complicado, etc., que está para acontecer.

• Get ready for the next stage.
• Prepare-se para o próximo estágio.

• Get ready!
• Prepare-se!

• Get ready to talk about it.
• Prepare-se para falar sobre isto.

• Brace yourself for the inevitable arguments.
• Prepare-se para as discussões inevitáveis.

Ainda existe a opção "gear up", comumente utilizada.

• Gear up for the holidays! (2017 Canada Games)
• Prepare-se para as festas!

• Gear up, guys!
• Preparem-se, pessoal!

Assista o vídeo a seguir com a expressão gear up (preparar-se em inglês).
Bons estudos.

Brace yourself = Se segure, seja forte, prepare-se; talvez até aguente firme.

Also

To get set

To start a race, children say: Get ready, get set...GO!

High-level yakuza member arrested for possession of 17kg of salt.
Is it possible to convict someone for possession of salt?

Surprisingly yes. This may be unique to Japan but in the event of a CCD, someone accepting a shipment of rock salt on the assumption that it’s an illegal narcotic can be convicted under Article 8 of the – get ready for this – Act Concerning Special Provisions for the Narcotics and Psychotropics Control Act, etc. And Other Matters for the Prevention of Activities Encouraging Illicit Conducts and Other Activities Involving Controlled Substances through International Cooperation.

Clouds Architecture Office has unveiled plans for a futuristic skyscraper dubbed the "Analemma Tower." The building would hover majestically above the ground because it would be attached -- wait for it -- to an actual asteroid, in space, that is forcibly put into orbit around the earth.