If you're out fishing, hunting or camping, a decent knife is essential. If you haven't honed the blade in a while, you can do it along the top edge of your vehicle's window.
YouTuber deermeatfordinner demonstrates the simple process of honing your blade in this video. Roll down the window of your car or ute and gently run the blade along the top of the window's rough edge. This will work the same as running the blade up and down a honing steel.
Just be sure to take it slow and be careful as you do so. Keep in mind that this won't actually sharpen the blade, but it will hone it. Sharpening and honing are two different processes, with honing being the process of realigning the edge of the blade so that it cuts more efficiently. If your blade is dull, honing won't do much to make it seem sharper.
The Best Knife Sharpener in the World [YouTube]