buy (yourself) time
buy time
To stall or delay in order to gain more time to do something. A noun, pronoun, or reflexive pronoun can be used between "buy" and "time," as can words like "more" and "some." I'm so sorry I'm running late to the party, but I'm almost there now—buy me some time so that I don't miss the cake-cutting! It's just such a big decision. What can we say to the bank to buy more time?
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
buy (yourself) time
If someone buys time or buys themselves time, they do something to give themselves more time. Knight was buying time while he considered his next move. He summoned the waiter, placed the order, and bought himself the time he needed.
Collins COBUILD Idioms Dictionary, 3rd ed. © HarperCollins Publishers 2012