If you want to get a few good years out of your spring bulbs, let the foliage dry up naturally-don't cut if off until it has lost all green color and looks spent. The bulb seeks nutrients-via photosynthesis-through the leaves and they need to do this so that they can bloom for you again next year. If you don't like looking at a mess of foliage consider planting some annuals among them that will hide the fading leaves. Or consider just living with it. A yellow stem and a brown leaf here and there isn't going to kill anyone-hopefully.
You don't need to fertilize the bulbs after they bloom. They'll be preparing for dormancy and they do this just fine on their own. Don't forget where you plant your bulbs if you're going to be doing planting this year. Photograph them or mark them so that you remember. Or not, if you like mysteries...If you are really into bulbs and want to learn more about them and their care here's a link to the international bulb society: http://www.bulbsociety.org/About_Bulbs/index.html