Rp Tutorials

I'm not sure if this has been answered before but how can I adjust Photoshop Color Manage Settings so that the image looks identical in PS as it does when I upload it online? I noticed my graphics look brighter in PS than they do when they're online (they look darker when uploaded). I've troubleshooted as much as I could online, but can't seen to find a solution or fix. Any help would appreciated! I have CS5.

If necessary, I will provide a side-by-side screenshot in Photoshop vs. darkened uploaded version side-by-side for reference.