1To make or manufacture something using materials and procedures; can also mean to rig up, concoct, or prepare (e.g., food, tools, plans).
彼女は夕食に簡単なスープをこしらえた。
She made a simple soup for dinner.
急いで壊れた机の脚をこしらえるために、工具を集めた。
I gathered tools to rig up a replacement leg for the broken table in a hurry.
子供たちは段ボールで秘密基地をこしらえた。
The children fashioned a secret base out of cardboard.
彼は言い訳をこしらえて上司に説明したが、すぐにばれてしまった。
He concocted an excuse to explain to his boss, but it was quickly found out.