"Making up the top head" is a phrase used to refer to brainstorming or coming up with ideas. When it comes to finding synonyms for this phrase, there are many options available. Some common alternatives include "idea generation," "creative thinking," "innovation," "conceptualizing," "ideation," "brainstorming," "concept development," and "ideating." All of these phrases refer to the act of developing new ideas, whether for a specific project or just in general. Whether you're a writer, artist, or business professional, finding ways to generate new ideas and think outside the box is an essential part of success.