In most cases, the process of changing and upgrading a lampshade is pretty simple and anyone should be able to do it. All you need to do is to measure the fitter size and make sure the new lampshade you want to swap it out for has the same fitter size. Then swap out the shade for the one you have chosen, and replace the screw. Does the lightbulb give off a particularly harsh light that doesn't contribute to the ambience of your home? If it's a like-for-like swap, it shouldn't be an issue, but it can make a huge different to the overall feel of your lighting.