The simplest way is to frame your image so you can crop the edges of your image.
Vignetting can occur with wide angle lenses because the field of view is so wide it captures the edge of the lens filter. There are a few things you can do to avoid minimise vignetting.
Before you start shooting, avoid stacking filters with your wide-angle lens. If you’re shooting with a CPL or ND filter, remove your UV filter. And try to use the correct fixed ND instead of stacking multiple ND filters. Note that variable ND filters have two layers of glass and can create more vignetting so they should be avoided. Avoid using a lens hood too as they can increase the chances of vignetting too. If you have a photograph you love but want to remove the vignetting, the best way to do so is to crop your image.