When looking for synonyms for the phrase "it's a good idea to do something", there are plenty of great options to choose from. For instance, you could say that "it's highly recommended" or "it's advisable" to take a certain action. Another option is to say that it's "wise" or "prudent" to do something, particularly if it's important or has the potential to impact your life in a significant way. Additionally, you might use phrases like "it's beneficial" or "it's advantageous" to describe why taking a certain action is a good idea. Regardless of the synonym you choose, the goal is to convey that taking a certain action is a smart and logical choice.