I use Photoshop Elements 8 for all post work/2D art/banners/buttons ect.....

Really for me it would be hard for me to explain if one wasn't using same program...(not sure what PI is?) ...not familiar with the slang....lol...sorry...

But if you....say .....were using Photoshop then all I do is create  a "new blank image"....in this case....(500 x 125)....and then choose what I'm going to place in the space.Then run it through (sometimes) as many as 25 to 50 variations of different filters until one clicks...save as a jpeg with as much clarity as possible and badda bing badda boom....finished...I know this is probably a weak tutorial and I apologize in advance....but it's basically the way I do it using Photoshop and is the best way I can explain it with what I know....(smiles)....