Its too much to just sum up for you so im just going to provide links to some reading. Generally you just need to up you calories and try to eat about 40% protein 40% carbs and 20% fat while bulking. You want complex carbs for the most part. Oats,pasta,brown rice, etc.etc.
http://forum.bodybuilding.com/showthread.php?t=3717251 BAM!!!
http://forum.bodybuilding.com/showthread.php?t=272067 POW!!!