Not bad @StuartNG, but the step of cropping the source before putting it through remove.bg is crucial to maintain image quality due to the fact that the free version of the site downscales any source provided to 500x500 (or equivalent in image dimensions). This means that, even when the original source is of a very high quality like this one, the fact the area taken up by the face is but a small proportion thereof means that the size taken up by the face is consequently correspondingly decreased leading to a loss of image sharpness once you then need to upscale it to get it to 250x250.

In short, crop the source before putting it through remove.bg if the face is a small better of the overall image and you'll get a better cut with a higher image quality.

How best to use remove.bg in conjunction with Photoshop:
https://streamable.com/tgfkx1