如何在JFrame中对齐comboPanel？

I am trying to create a simple GUI using NetBeans. I have multiple comboPanels in my JFrame, but I cannot seem to fit them properly. I have the tried using BorderLayout.NORTH, SOUTH etc. but they end up overriding each other or just discombobulated in general. Below is the code I am using for the comboPanel. I have tried re arranging and playing around with the positioning but no luck. I am trying to create a simple GUI using NetBea