If some triggers cannot be avoided be prepared to treat the migraine as soon as symptoms present themselves. Many triggers are foods and food additives. Avoid these items. Take medications as prescribed. Preventative medications must be taken regularly, as prescribed, in order to be effective.
Prescription medications taken as needed are often most effective if taken early.
Second hand smoke can be a trigger which can be avoided. Maintain a regular schedule. Eat meals at the same time daily. Get the same amount of sleep each night. Missed meals and either too much or too little sleep can trigger migraines.