So basically, once I am done making a Twitter header (in Photoshop) and I have saved it as JPEG, I go to upload it as my new Twitter header; but when I do, the quality always decreases.

I mean that the quality is fine in Photoshop but when I put it as my header in Twitter it gets decreased.

I'm not sure what to do as I've tried pretty much everything. I've tried a new resolution(s), I've tried making the actual image smaller but nothing seems to be working. It is starting to frustrate me as I am proud of the work I am producing but the quality decreases which make it seem as if I put no effort into the work.

If anyone has a solution to this I will be very happy, thanks guys!