
The biggest temptation for a new designer is to show everything they can do. At the start the opposite is better: a small, coherent collection that you know how to sell.
Draw a table with three columns: hero, supporting, test. Give each piece a working name, fabric, color and target price. If you have more than ten pieces, remove until you are back to the number you can fund. The collection planner in the toolkit does this for you.