おくこと

doing in advance

→ おく
phrase Uncommon #11,992
doing in advance Often follows a verb in the て-form to indicate doing something ahead of time or making sure it is done.
JA: 旅行の前にホテルを予約しておくことが大切です。
EN: It’s important to book a hotel in advance before a trip.

彼女が自発的に止めるまで、放っておくことに私達は決めた。

We decided to leave her alone until she stopped on her own.

身辺の整理をしておくことだな

I suppose I should get my affairs in order.

— AKIRA (1988)

まずは、キラが『海賊』に襲われるかもしれない、とほのめかしておくことだ。

First, we should hint that Kira might be attacked by the “pirates.”

いいか始める前に他に話しておくことは?

All right, before we begin, is there anything else we should discuss?

— オープン・ユア・アイズ (1997)

彼は最悪の事態に備えておくことが必要だ。

He needs to prepare for the worst.

ドアの鍵はかけておくこと。

Make sure to lock the door.

自分の持ち物には全て名前を書いておくこと。

Make sure to put your name on all your belongings.