I'll go ahead and post the steps, as many will look for that information here:
1. Alt+click on empty space while in the Galaxy Map. This will bring up the Context Menu, a dropdown menu.
2. Click on "Galaxy Layout".
3. Click "My Layout".
If you see a green/red flashing "Your Alternate Galaxy Layout" on the bottom right hand corner of the screen, then you are ready to untangle! As others have mentioned, hold shift and drag planets to relocate them as desired. This makes complex maps much easier to comprehend.