I recommend starting by thoroughly understanding your brand before opening any design software. Think about the business of your geometry dash, your target audience, and the impression you want the logo to create. Once you’ve determined that, sketch out a series of preliminary ideas on paper – don’t worry about them being perfect.
After you have a few ideas, refine the best ones in vector editors like Figma, Inkscape, or Illustrator. Keep the design simple and ensure it still looks good in black and white or at small sizes.