i actually happen to be a huge fan of this effect myself. here- on whatever object you wwant to add a glare (a orb for example) take the tool selection (for a orb make it the circle selection) and place it however large, and whever you want the glare to be. then use your gradient tool with your primary colour set to full white, and your secondary to fully transparent, drag it down through the circle you made with the selection tool. then diselect and blur it a little. i
(i know that wasnt realy good but if you can make some understanding out of it, then thats all you realy should need to know, or at least the basics.)