I was never proficient with Photoshop (or its open-source derivatives) and I still don't know jack about it. However, because of some web design work I got myself into lately, I now move a little more freely about. One thing however that has eluded me forever was how to apply a 1px border around an image or a banner, in this particular case. So, here's a quick recipe I found somewhere on the interweb...

Create a new layer

Press Command+A (or Ctrl+A on the PC) to select all. Then go to Edit->Stroke and apply the following settings: Width: 1px. Color: Black. Location: Center. Blending Mode: Normal. Opacity: 100%

Of course your mileage may vary so you should adjust these settings to your particular need. Here's the small banner I created for this blog featured this 1px border:

This comes along with some cosmetic changes to the site. Hope you enjoy it, feedback welcome!