Hi Lauren,
Good work for your first M42.
It appears a light pollution problem, with you clipping the images black side to reduce the lighting from the captured sodium element.
How to get more colour? You need a darker site, or higher image processing skills. Processing skills come with experience and guidance, but this will never substitute for a dark sky site. So, find a safe dark site, and try again.
Your focus and tracking looks good.
Steve
