To pass on something; to give something a miss (decide not to do or accept it for now).
その会には今回はやめておく。
I'll pass on that meeting this time.
高いからデザートはやめておくよ。
The dessert is expensive, so I'll give it a miss.
新しいスマホは買いたいけど、今回はやめておく。
I want a new phone, but I'll skip it for now.
To stop or let something drop (to cut it out, to knock it off, or to leave the matter alone).
今日はこれでやめておく。疲れたから。
Let's quit for today. I'm tired.
その冗談はもうやめておくべきだ。
You should stop that joke now.
その件は一旦やめておくことにした。
I've decided to drop that matter for the time being.