"慢条斯理地做事" can be translated into English as "to do things in a slow and deliberate manner" or "to work at a leisurely and unhurried pace".
Both expressions convey the idea of performing tasks calmly, without rushing, and with a focus on thoroughness rather than speed. Here are some examples of how these phrases might be used in a sentence:
He always does things in a slow and deliberate manner, ensuring nothing is overlooked.
（他做事总是慢条斯理，确保不会遗漏任何细节。）
She worked at a leisurely and unhurried pace, enjoying every moment of the process.
（她以一种悠闲而不急躁的节奏工作，享受着过程中的每一刻。）