You can spend $5 on a mass produced cover made of fake leather.
But I don't like fake leather, so I made my own cover from vegetably tanned reindeer leather.
Colored it charcoal to match the crawler's details. Hand stitched with linen thread and used a regular paintbrush to add the text. Then applied some leather oil to finish the job.
The "spare wheel" is fake though. Underneath the cover is a 2.2" racing rim that I carved away lots of material from to make it lighter, and a simple foam to hold the cover in the shape of a wheel. This way it's as light as possible and the least intrusive on the driving.
But I don't like fake leather, so I made my own cover from vegetably tanned reindeer leather.

Colored it charcoal to match the crawler's details. Hand stitched with linen thread and used a regular paintbrush to add the text. Then applied some leather oil to finish the job.
The "spare wheel" is fake though. Underneath the cover is a 2.2" racing rim that I carved away lots of material from to make it lighter, and a simple foam to hold the cover in the shape of a wheel. This way it's as light as possible and the least intrusive on the driving.