This article will teach you how to set up your budget rule
From the Budget column in the Campaign tab, open the drop-down menu > Actions:
Set, Increase or Decrease your budget based on performance.
For example, you can set a rule to increase budget by certain $ or % where Conversions are greater than 10. You may set a condition and your upper budget limit.
Next step is to save the rule as a “View” and Execute/schedule a task:
While you are on the view that you created, go to Publish > Execute/schedule a task:
Execute will run this action once.
Schedule a task will allow this job to reoccur in your selected time frame.