Okay, this effect will make your graphic look like it's shiny or glossy. And as we all know, everybody wants shiny things, it lies in the human nature. First open a new document, I use 500x500 pixels. Then make a selection with the rectangular marquee tool (or use hotkey M).
Make a selection like mine. (I've added a smooth effect on the edges. Just make your selection and go to the selection menu on the top of the page, then select-modify-smooth. Use smooth 5 to get my result).
Now make a new layer, empty. On the top of your screen you choose layer-new-layer or hotkey command+n/ctrl+n. Now choose your paint bucket tool (hotkey G) and fill the shape with any colour of choise. Don't deselect the selection. Now go to select (on the top of your screen) and choose selection-modify-contract. I used 2 px and got this.
Now i want you to make a new layer (command+n/ctrl+n) and fill this new layer with a basic white gradient. Like this. The way to do this is when you have made the new layer is to right click on the paint bucket tool, and in the new menu choose the gradient tool. Now drag a gradient from top to bottom. Then you will get this.
Lower the opacity on the last layer to about 80 %, (click on the numbers on your keypad, like 1,2,3,4 also. Hit the 8 key to get 80 % opacity).
Now you will have a light version off the shiny effect. If you use this right it will look great. It doesn't look too good in my example I'm afraid. But I promise you this will look good when used in the right places. Try it out!
