There are numerous synonyms for the phrase "making trouble," including but not limited to: stirring up mischief, causing havoc, instigating chaos, fomenting unrest, inciting commotion, provoking turmoil, sowing discord, creating turbulence, arousing dissent, and generating disruption. Each of these phrases speaks to the idea of intentionally causing problems or unrest, and can be used in a variety of contexts. Whether you are referring to a mischievous child or a political activist, there are many ways to describe someone who is making trouble, depending on the tone and level of severity you wish to convey.